This is 1 bug I always encounter: in the MS-DOS Doom1 E1M6 in the maze-like part, there's a zombieman who somehow appears outside te walls, forever haunting nobody. If that happens, you can't reach 100% kills without idspispopd.
my favorite fact about this bug is that chocolate doom has a different memory layout (so it wouldn't work the same way), so instead, chocolate doom *manually* recreates the effect by overwriting the appropriate variables in the same order
@@raulsalcedo8332 The only thing that is given an exception to Rule 34 is if its a citation of Rule 34 also called Rule 35. Otherwise no because it is something that is concieved making it exist so it is under Rule 34. (Unfortunately...)
Keep in mind this only happens in Doom ports that: 1) Share similar memory addresses; 2) Don't fix ray cast rounding errors; 3) Don't fix the intercepts array overflowing. PrBoom+ for example can only emulate the all-ghosts effect behaviour, but it doesn't actually directly overwrite memory through the intercepts array.
I love how on the surface, Doom is "shoot it until it dies" but underneath there's a bunch of quirks like this. And then you have ASMR doom pumpkin man explaining it to you. Better than uni
I hate that it exists in Eternity and cannot be turned off in the compatibility options. Forgive me skillsaw, but I ain't completing Heartland until that happens.
Coming back after Zero Master used the insights from this video to get new world records in E1M8 and Plutonia map 11. Congratulations, decino! You deserve a Nobel prize in Doom science.
9:20 so how does Zero Master do it reliably enough to use? OK I see his explanation in the description of his video. Basically his brute force method was using inputs that he could replicate without TAS. Still I wonder how precise do the inputs have to be? His video: th-cam.com/video/P01d-AmqByU/w-d-xo.html
@@YogiTheBearMan Karl Jobst has covered Zero Master's technique here: th-cam.com/video/T_5ZYJBgQyM/w-d-xo.html He explains that Zero Master's simulations performed about 300 years of gameplay to find the solution. Great video.
@@Drahcir_XIII still doesn't explain how he went from discovering a random string of inputs that happened to activate the glitch to implementing it in an rta run, like did he figure out a way to do it consistently and if so how
@@aclonymousthe video does explain it. The 300 years of game simulated was used to run a simple string of inputs constantly to try and find the values for the bug to happen. Basically the simulation did the inputs than ran into a wall, if it ran into the wall, it would reset. it kept on doing that until it went through the wall the inputs given were simple. Would have been something like, move forward 20 map units, shoot 3 times, turn to the right, shoot again and then go into the wall. Because they were simple enough inputs that a person could do it, ZeroMaster just replicated the inputs
"The only way to exit the level is through a death exit damaging floor." Dude, that is obscure as hell. You're amazing at analyzing the Doom engine and pushing it to its limits. I don't think anyone has ever gone this far and this deep. I always get happy when you release a new video like this.
Well i mean doom's ray tracing only takes into account anything on the x or y axis since those are the only two axes you can aim and shoot on that have anything to intercept your bullets with so it's kind of obvious why pools and damaging floors can still hurt doomguy,
I love that, despite Doom being a game older than a significant part of TH-cam's overall userbase, you've still managed to build an entire channel primarily on the game's myriad quirks. Also, at 10:01, is that Mr. Bones' Wild Ride on the right? Nice subtle nod to another legendary old game.
The series is still getting new releases, and I think they even put at least one of the old ones in Eternal; there's the Unity port for everyone on console as well, and it's dirt-cheap (5 bucks for each game, and it goes on sale sometimes), and it's shaped up to be a very respectable source port (as opposed to the disaster it launched as) and even include a bunch of prominent WADs as well. Doom is arguably more accessible now than it's been since its heyday, even the most tech-illiterate person can just buy it, download and play.
@@hoodedman6579 Yep! When I heard doom eternal was coming out, I bought doom 2016, and after that decided to play through doom 1 and 2 before it released. I had _heard_ of doom before, but had never sat down and played it. I'm now a big doom fan even working on a custom 7 map wad, and after that's done I'm going to give final doom a go.
@@kingkuma4112 Nice! That's quite the dedicated fan you've become! Is there a place I can follow your progress on your wad, perhaps? Maybe reply to this comment chain when it's done?
I remember seeing this exact bug in one of Altimamantoid's outtakes with TNT Map 22 ten years ago. It happened right in the middle of his rant about awful the map was and it killed him within seconds.
Well that and it was a community map that was never meant to be bought so having TNT Evilution's quality go south in the middle towards the end of the megawad would have been fine if it was released for free like it was planned to. Honestly i would have been fine with just the plutonia experiment as final doom.
@@michealpersicko9531 For the most part, I enjoyed TNT Evilution. Most of the levels are creative and interesting, and pushed the engine in various directions. Also, it's not like the original doom2.wad was the greatest thing either. No one had yet truely mastered the art of Doom map making, the tools at the time were poor, and computers couldn't handle anything beyond simple map geometry with only a handful of enemies onscreen at a time. Now, I personally dislike Plutonia. It seems to love putting hitscan enemies and archviles in places that are very awkward to aim into or hidden, so that you take a bunch of unavoidable damage if you don't have the proper approaches memorized, and has too many combat arenas where movement is downright awkward. Also, the architecture is, with a few exceptions, rather bland and repetative. Where in TNT you never know what sights you'll see around the next corner, with Plutonia it will surely be more brown walls with green vines and chaingunners. I've played through all of TNT twice. With Plutonia, I started two or three times, but never got past the second or third level before getting bored and annoyed and dropping it.
@@michealpersicko9531 Plutonia and Evilution are a perfect pair -- for people like me who hate Plutonia's high-difficulty, short-length maps and prefer to actually spend time exploring without running like a blue-assed fly from revenant missiles. Either one alone would leave a chunk of players disappointed.
@@YourTypicalWarp No idea why this comment has any likes, that's so untrue. Spectres have always existed in Doom. No idea where you got the idea that this insanely rare bug that likely wasn't discovered until some time after Doom II or even Final Doom released -- would be named as a "ghost" bug because spectres didn't exist... It's because you literally act like a ghost. You can go through walls and are barely able to have any interactions at all. Spectres can interact with the environment... and attack.. and be hit. So what way is this remotely similar to how Spectres function....? The weird bullshit some of you guys say is insane.
whoa, look, i was just misunderstood, i thought he was talking about the spirits from doom eternal :\ now, instead of starting an insanely dumb argument, i misunderstood the enemy and i apologize!
Glad Karl pointed me towards this video and your channel. Super cool videos! Just insane that your video about this glitch, and your breakdown was eventually used to actually find a practical use for this bug, and used to break another Doom speed run! Leave it to you crazy talented maniacs to find out how this all works, and how to exploit and activate these glitches, even if it takes years to do so! Congrats to you all!
Me like 45 minutes ago: "Huh, there hasn't been a decino video in a few weeks now..." Me, just now, opening youtube again: "Decino video uploaded 34 minutes ago" impressive
"Hmmm, decino hasn't posted a video in a while, I hope he's ok." "Y'know, he's probably fine, just working on a yellow video" -me for the last 2 weeks Good to see you're still with us and not a spooky ghost lol
Apparently this glitch also happens when trying to load a massive map, but it happens differently depending on the source port. GZDoom does turn enemies into ghosts, but vanilla compatible ports make the monsters solid but invincible. Really weird
@@theraymunator Sourceports may emulate the all ghosts effect in some way or another. Vanilla compatible sourceports will behave very similarly to original game in such event, where intercept array starts overwriting unrelated memory. All it takes is for the hitscan shot to go through a lot of targets.
5:28 Damn that’s a cool way of getting around that, looking forward to maybe seeing it as another “practically possible” addition in “Doom Challenges Deemed Impossible Update Update”
It's like this is a glimpse of the true form of noclip, where not even projectiles can interact with you... I love how much effort you put into these obscure quirks and trivia from a game that seemingly has risen in popularity once more after decades of being extremely niched. Thank you ducino, and cheers!
Funnily enough, before there was research done into why this bug happens, it was known to deathmatch players as something along the lines of "the DM noclip bug", because if there's no monsters around it just looks like everyone turned on noclip at the same time.
@@LonelySpaceDetective But even that is kind of a misnomer, because noclip doesn't prevent you from flipping switches and it doesn't stop your projectiles from colliding too.
This leads to the very mysterious question: "Who asked?" Well, to understand the question, we have to understand the answer: So this very particular question is asking about who asked, the question is divided into two parts: Who & asked "Who" is what is called an "Interrogative word" which specifies the answer to make it suitable for the question, the "Who" here is specifying a person/human/homo sapiens/guy which has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human. Second: "asked" is a verb in the second condition of the forms of the verb, which are divided into three types: Regular, Past, or Past participle. and the verb "asked" is in the "Past" condition, which talks about the time that is gone and no longer exists. The original form of this particular verb is "ask", which is to say something in order to obtain an answer or some information. So, to summon what the answer wants from the previous two points, it's that: The answer wants to understand and know about the person/human/homo sapiens/guy who wanted to say something in order to obtain an answer or some information. So, in order to answer this question, we will have to identify two points: First: What was the question that the subject of the answer to the question "Who asked?" asked? Well, to understand this question, we will NOT have to understand what is the answer. We will just have to understand the definition of "Question" The "Question" is A sentence worded or expressed so as to elicit information. Questions could be identified using the "Interrogative Words", which we talked about earlier. these "Interrogative Words" are nine, which are: Who, What, Where, Why, Which, When, Whose, Whom, and How. We are going to explain each individually: As we said earlier: "Who" is specifying a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human. "What" is specifying a non-person/non-human/non-homo sapiens/non-guy who either does not have a brain that he can understand and think properly with, like plants, or objects, or they have a brain, either that their brains cannot understand and think properly, like animals, or their brain can understand and think properly, but their species/type is rather different from the society, like extraterrestrial creatures, so the answer should be as I said in the abstract: A(n) animal, plant, extraterrestrial creature, or object. "Where" is specifying a place, city, country, continent, etc. where something happens, or some(one/person/human/homo sapiens/guy), plant, animal, extraterrestrial creature or object which exists in a place, city, country, continent, etc. "Why" is specifying a reason for doing something. "Which" is specifying a choice of either two or more choices that the receiver of the question usually chooses. "When" is specifying a time in which either something already happened, or something will happen in either near, or far future, for example: "When will anyone save me as I was captured by MatPat for trying to comment a joke about his video?" "Whose" is specifying a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, and that person/human/homo sapiens/guy owns something, or someone ( if he is a human trafficker ), and the sender of the question is trying to find who owns that something, or someone. "Whom" is an old-fashioned term, not often used today. Many native English speakers are less than clear about its accurate use. In fact, the word serves the same purpose as "Who" questions, which as we said: specifies a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human, but tends to be used when it is the object of the verb. With modern English, there is no real need to use the term. "How" could be referring to the way something is done or refers to the status of the receiver of the question. Now, let's get back to where we were talking: Questions can be different, and many, and the possibility of guessing the question could be high or low according to the frequency of using it, but guessing a question which was asked for the first time is very difficult, so, it is not specific what was the question that the subject of the answer to the question "Who asked?" asked. Second: What is the purpose of the question "Who asked?"? Well, it could be referring to roasting someone as the humor of "No one asked.", and it could be referring to actually asking a question about who asked the question. So, here's the answer to the question "Who asked?": It could be anyone who made something unlikely for the others or someone who asked a question which could be a hint to treasure, or a last "sentence" from somebody, or something else. (s)He could be you. (s)He could be me. (s)He could be Elon Musk. (s)He could be even your mom. as long as they have made something unlikely for the others or they have asked a question which could be a hint to treasure, or a last "sentence" from somebody, or something else.
I've played the classic doom games since they came out. Never have I managed to see this bug happen. This is why I enjoy this channel, it shows how much there still is to find in old Doom
I saw Karl's video and was like "wait, I could have sworn I had seen a video on this before..." then Karl directly quoted this video and I was like "oh right, that was where!"
This video is ground-breaking. The 128+ things intercepts overflow isn't a mystery to many people, but what you explained at 7:00 was outright fascinating, it is new knowledge for me, and I believe for the community as a whole too. I've been wondering about this for so long... I never thought I'd see a fixed-point-value precision error having such massive consequences. But I disagree with you: I believe that, in light of this information, the speedrunning community might be able to use this to trigger the bug on demand, even on maps where there aren't 128+ things in a line. How? First, you can use a corner + take as-small-as-possible steps (single-tic moves) from that corner to get to a fixed position. Second, with shorttics you can easily and consistently turn to a fixed angle. So from this day forwards, discovering setups to trigger the all-ghosts bug on demand is much more feasible. What will the speedrunning community achieve with this? No idea, but I can't wait to find out! :) As always, amazing stuff decino!
Thanks Coin, that means a lot to me. I may have done it wrong (and didn't spend much time on it honestly), but every time I hugged a corner the fractional values would differ slightly. We were already discussing on Discord to write a program or simulation that brute forces a bunch of precise coordinates and angles to see where you can overflow the intercepts on demand. Useful for TAS demos for sure.
The way it moves the offset past where it should be is similar to items over 99 in gen1 pokemon. The gameboy has two sets of tilemaps that overlap. At the end of the overlapping parts are the numbers for the interface. So if you have 100 of something, the "10" is just the tile directly after the tile for "9", which is part of the map you're walking in. And the missingno glitch increases the item in the 6th slot of your inventory by 128, moving it past 99 into the map geometry. But no ghost mode there, it's just a pure interface issue, the system can handle item counts up to 255 without issue. Since 99 + 128 is less than 255, you will never run into a size that would cause issues. So while the utility of both are different, both work in a similar way, moving data into areas where they shouldn't be.
@@TheDoomer666 If you are spelling the name in English it will only be Vietnam without space between However the Vietnamese writes it as Việt Nam or Viet Nam with space between In Vietnamese, names such as of humans, animals and countries are written with capitalized at the start of each syllable: America=Hoa Ki or My/Mi China=Trung Quoc based on the Chinese spelling Zhongguo Korea=Han Quoc(Hanguk) and Trieu Tien(Chosun)...
@@vietnamgaminghm whoa bro, did you just revisit this video randomly? or are you responding to every notification after coming back from the dead lol thanks for the explanation tho! 👍
Ive been paying doom for over 15 years, never in my live heard of this, marvelous how Decino never stops surprising me with new things every video. Amazing
When I was a kid I used to accidentally trigger this bug on Plutonia's MAP30 by waking up the Icon, turning on god mode, and then seeing if I could fill up the entire map with monster bodies. After a while of doing this they started noclipping and I couldn't kill them. I always just assumed I overloaded the game with too many enemies.
Yeah, I ran into this bug the same way back in the day (though in my case it was on Doom 2's MAP30). As much as I like understanding how and why it happens, it still takes some of the magic out of it. :P
I actually encountered this for the first time quite recently... just a few months ago while playing through TNT Evilutuion in Map 09: Stronghold. At the time I had no idea what it was, and assumed I'd triggered the void glitch somehow by accident (i.e. the one speedrunners use in Doom 1's Halls of the Damned to get to the exit). But now that I've seen this, and given the large enemy count for that map (at least by 1996 commercial Doom IWAD standards), now it makes sense how I triggered this bug. If anyone wants to mess around with that map... I think(?) I was in the southwest portion of the map, but like I said, it's been a few months now, so I could be remembering wrong.
This leads to the very mysterious question: "Who asked?" Well, to understand the question, we have to understand the answer: So this very particular question is asking about who asked, the question is divided into two parts: Who & asked "Who" is what is called an "Interrogative word" which specifies the answer to make it suitable for the question, the "Who" here is specifying a person/human/homo sapiens/guy which has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human. Second: "asked" is a verb in the second condition of the forms of the verb, which are divided into three types: Regular, Past, or Past participle. and the verb "asked" is in the "Past" condition, which talks about the time that is gone and no longer exists. The original form of this particular verb is "ask", which is to say something in order to obtain an answer or some information. So, to summon what the answer wants from the previous two points, it's that: The answer wants to understand and know about the person/human/homo sapiens/guy who wanted to say something in order to obtain an answer or some information. So, in order to answer this question, we will have to identify two points: First: What was the question that the subject of the answer to the question "Who asked?" asked? Well, to understand this question, we will NOT have to understand what is the answer. We will just have to understand the definition of "Question" The "Question" is A sentence worded or expressed so as to elicit information. Questions could be identified using the "Interrogative Words", which we talked about earlier. these "Interrogative Words" are nine, which are: Who, What, Where, Why, Which, When, Whose, Whom, and How. We are going to explain each individually: As we said earlier: "Who" is specifying a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human. "What" is specifying a non-person/non-human/non-homo sapiens/non-guy who either does not have a brain that he can understand and think properly with, like plants, or objects, or they have a brain, either that their brains cannot understand and think properly, like animals, or their brain can understand and think properly, but their species/type is rather different from the society, like extraterrestrial creatures, so the answer should be as I said in the abstract: A(n) animal, plant, extraterrestrial creature, or object. "Where" is specifying a place, city, country, continent, etc. where something happens, or some(one/person/human/homo sapiens/guy), plant, animal, extraterrestrial creature or object which exists in a place, city, country, continent, etc. "Why" is specifying a reason for doing something. "Which" is specifying a choice of either two or more choices that the receiver of the question usually chooses. "When" is specifying a time in which either something already happened, or something will happen in either near, or far future, for example: "When will anyone save me as I was captured by MatPat for trying to comment a joke about his video?" "Whose" is specifying a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, and that person/human/homo sapiens/guy owns something, or someone ( if he is a human trafficker ), and the sender of the question is trying to find who owns that something, or someone. "Whom" is an old-fashioned term, not often used today. Many native English speakers are less than clear about its accurate use. In fact, the word serves the same purpose as "Who" questions, which as we said: specifies a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human, but tends to be used when it is the object of the verb. With modern English, there is no real need to use the term. "How" could be referring to the way something is done or refers to the status of the receiver of the question. Now, let's get back to where we were talking: Questions can be different, and many, and the possibility of guessing the question could be high or low according to the frequency of using it, but guessing a question which was asked for the first time is very difficult, so, it is not specific what was the question that the subject of the answer to the question "Who asked?" asked. Second: What is the purpose of the question "Who asked?"? Well, it could be referring to roasting someone as the humor of "No one asked.", and it could be referring to actually asking a question about who asked the question. So, here's the answer to the question "Who asked?": It could be anyone who made something unlikely for the others or someone who asked a question which could be a hint to treasure, or a last "sentence" from somebody, or something else. (s)He could be you. (s)He could be me. (s)He could be Elon Musk. (s)He could be even your mom. as long as they have made something unlikely for the others or they have asked a question which could be a hint to treasure, or a last "sentence" from somebody, or something else.
Learned something new today. These series on how the doom code work are really interesting. I'd love to see some breakdowns for more contemporary engines.
This leads to the very mysterious question: "Who asked?" Well, to understand the question, we have to understand the answer: So this very particular question is asking about who asked, the question is divided into two parts: Who & asked "Who" is what is called an "Interrogative word" which specifies the answer to make it suitable for the question, the "Who" here is specifying a person/human/homo sapiens/guy which has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human. Second: "asked" is a verb in the second condition of the forms of the verb, which are divided into three types: Regular, Past, or Past participle. and the verb "asked" is in the "Past" condition, which talks about the time that is gone and no longer exists. The original form of this particular verb is "ask", which is to say something in order to obtain an answer or some information. So, to summon what the answer wants from the previous two points, it's that: The answer wants to understand and know about the person/human/homo sapiens/guy who wanted to say something in order to obtain an answer or some information. So, in order to answer this question, we will have to identify two points: First: What was the question that the subject of the answer to the question "Who asked?" asked? Well, to understand this question, we will NOT have to understand what is the answer. We will just have to understand the definition of "Question" The "Question" is A sentence worded or expressed so as to elicit information. Questions could be identified using the "Interrogative Words", which we talked about earlier. these "Interrogative Words" are nine, which are: Who, What, Where, Why, Which, When, Whose, Whom, and How. We are going to explain each individually: As we said earlier: "Who" is specifying a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human. "What" is specifying a non-person/non-human/non-homo sapiens/non-guy who either does not have a brain that he can understand and think properly with, like plants, or objects, or they have a brain, either that their brains cannot understand and think properly, like animals, or their brain can understand and think properly, but their species/type is rather different from the society, like extraterrestrial creatures, so the answer should be as I said in the abstract: A(n) animal, plant, extraterrestrial creature, or object. "Where" is specifying a place, city, country, continent, etc. where something happens, or some(one/person/human/homo sapiens/guy), plant, animal, extraterrestrial creature or object which exists in a place, city, country, continent, etc. "Why" is specifying a reason for doing something. "Which" is specifying a choice of either two or more choices that the receiver of the question usually chooses. "When" is specifying a time in which either something already happened, or something will happen in either near, or far future, for example: "When will anyone save me as I was captured by MatPat for trying to comment a joke about his video?" "Whose" is specifying a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, and that person/human/homo sapiens/guy owns something, or someone ( if he is a human trafficker ), and the sender of the question is trying to find who owns that something, or someone. "Whom" is an old-fashioned term, not often used today. Many native English speakers are less than clear about its accurate use. In fact, the word serves the same purpose as "Who" questions, which as we said: specifies a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human, but tends to be used when it is the object of the verb. With modern English, there is no real need to use the term. "How" could be referring to the way something is done or refers to the status of the receiver of the question. Now, let's get back to where we were talking: Questions can be different, and many, and the possibility of guessing the question could be high or low according to the frequency of using it, but guessing a question which was asked for the first time is very difficult, so, it is not specific what was the question that the subject of the answer to the question "Who asked?" asked. Second: What is the purpose of the question "Who asked?"? Well, it could be referring to roasting someone as the humor of "No one asked.", and it could be referring to actually asking a question about who asked the question. So, here's the answer to the question "Who asked?": It could be anyone who made something unlikely for the others or someone who asked a question which could be a hint to treasure, or a last "sentence" from somebody, or something else. (s)He could be you. (s)He could be me. (s)He could be Elon Musk. (s)He could be even your mom. as long as they have made something unlikely for the others or they have asked a question which could be a hint to treasure, or a last "sentence" from somebody, or something else.
I encountered this bug once as a kid. I don't remember which map it was but I remember never wanting to play that map again because of how creepy it was. It makes me wonder what kind of interesting things you can do with this bug that haven't been discovered yet
Bad luck? Speedrunners would like to disagree with that, they'll find a way just like life xD Always to see Decino's analysis, it could be entertaining and educating at same time
Wana get good at doom?: Watch a video with a funny yellow color. Wana know how to code?: Watch a video with a funny yellow color Wana know how was doom created?: Watch a video with a funny yellow color Wana know how graphics were made for doom?: Watch a video with a funny yellow color. Wana know how were SFX things made for doom?: Watch a video with a funny yellow color. Wana know how weapons work in doom?: Watch a video with a funny yellow color Wana know how powerups work in doom?: Watch a video with a funny yellow color Wana know how armor works in doom?:Watch a video with a funny yellow color. Need demon tierlists for doom?: Watch a video with a funny yellow color. Wana know enemy stats for doom?: Watch a video with a funny yellow color Wana know seroius sam stuff?: Watch a video with a funny yellow color. Wana know how shield suits work in doom?: Wana get good at doom?: Watch a video with a funny yellow color. Wana know how to code?: Watch a video with a funny yellow color Wana know how was doom created?: Watch a video with a funny yellow color Wana know how graphics were made for doom?: Watch a video with a funny yellow color. Wana know how were SFX things made for doom?: Watch a video with a funny yellow color. Wana know how weapons work in doom?: Watch a video with a funny yellow color Wana know how powerups work in doom?: Watch a video with a funny yellow color Wana know how armor works in doom?:Watch a video with a funny yellow color. Need demon tierlists for soom?: Watch a video with a funny yellow color. Wana know enemy stats for doom?: Watch a video with a funny yellow color Wana know seroius sam stuff?: Watch a video with a funny yellow color. Wana see if pacifist runs and chalanges are possible in doom?: Wana get good at doom?: Watch a video with a funny yellow color. Wana know how to code?: Watch a video with a funny yellow color Wana know how was doom created?: Watch a video with a funny yellow color Wana know how graphics were made for doom?: Watch a video with a funny yellow color. Wana know how were SFX things made for doom?: Watch a video with a funny yellow color. Wana know how weapons work in doom?: Watch a video with a funny yellow color Wana know how powerups work in doom?: Watch a video with a funny yellow color Wana know how armor works in doom?:Watch a video with a funny yellow color. Need demon tierlists for soom?: Watch a video with a funny yellow color. Wana know enemy stats for doom?: Watch a video with a funny yellow color Wana know seroius sam stuff?: Watch a video with a funny yellow color.
thanks decino, as a software engineer its awesome hearing the detailed explanation of these bugs, nothing like a good old array index out of bounds / overflow
Huge thanks for this informative video! I feel like it might not get as many views as your other analysis videos, but boy, was it a real treat to watch. Looking forward to more coverage of obscure bugs!
Decino, I was furloughed for basically all of 2020 and I found your channel at the beginning of quarantine right after I beat DOOM, 2, 64, and 2016. I love watching all your videos and your play series, especially when you tried DOOM 64. I started working a new job in February and I have missed so many videos unfortunately. I just opened TH-cam and I saw the yellow background for this video and got so excited; I felt like I was pulled back to 2020 for a second in a good way. I just wanted to get weirdly sentimental and say thank you for keeping me sane through that crazy year :)
Karl brought me back here today and i'm nerding out with the numbers (and my half a physics degree lol), the 9 significant figures required to recreate the effect you describe at 9:19 i mean, it's literally more accurate that the B I G announcements that the large hadron collider has made over the past decade (six sigma is regarded as HUGE STATISTICALLY RELEVANT NEWS with 8 sig fig)
I've been playing Doom since its release. Today (2024-09-24), for the first time ever, I encountered the ghost bug on a Sunder map. Fun fact: it took me a while to realize it was the ghost bug because there were sooo many monsters in just a very big room. I was at a stage where Revenants were on an upper platform with no way to come down. Suddenly, I saw them right in front of me and thought, 'How the hell did you guys get down here?' That’s when I finally realized it was the ghost bug, FINALLY after 30 years 😅
Always good to see another video from you decino. Also grats on 130k, I'm looking forward to whenever the next Sunder stream will be as you got some amazing levels coming up. Also I recommend anyone who enjoys decino's doom wad playthroughs, especially the difficult ones, to subscribe to A1s(the link in this video description) as his content is fairly similar.
I encountered an invincible Shotgunner while playing Co-op in the DOOM + DOOM II port, It was "The Express Elevator to Hell" in the Master Levels. Now, watching this video, it seems like it was the Arch-vile Resurrect Glitch. That was very fun to encounter at the end of that map.
Thank you so much for making this analysis video, decino! I had mentioned to you previously that I was pretty familiar with the intercepts overflow, but I still didn't know all the specifics regarding things like how many intercepts were needed to cause the all-ghosts effect. I've encountered the overflow dozens of times in the past few months (not including intentionally triggering it) and I've seen it cause different issues at times. Perhaps the following info will be useful to you and also explain what happens when too many intercepts occur (some people were asking about that in the comments and I have the answer :D). On one of my own maps, the overflow was very easy to trigger (too many linedefs for extra lighting variation). However, it seemed to be incredibly minor and I was unable to notice any issues with gameplay. The only reason I knew it occurred was thanks to PrBoom+'s optional warning message (very handy for playtests!). The player starts could get messed up in cooperative if a few player corpses were lined up with the ceiling lights. I fixed this as soon as I discovered it on that map by reducing the amount of lighting variation slightly :D The epic slaughtermap, Heck on Earth (the one I mentioned with the ghost funnies :D), from my upcoming megawad does have a small chance for the all-ghosts effect. It's situational as it'll require a lot of monster corpses to be lined up, but with 1,080 monsters that's definitely not too difficult. The map gives the monsters plenty of room to move around so this should be very rare and I have tweaked it to help reduce the chance (I also playtest my maps 100+ times for quality assurance :D). Before tweaking it, I encountered the overflow again, but this time it seemed to make collision less precise, although the map was still playable. I mean, 7 SSG shots to kill an Arachnotron when you're right up in his face is definitely not just bad RNG and the blockmap bug :D The intercepts overflow is guaranteed to crash vanilla DOOM if there are too many additional intercepts. As far as I know, PrBoom+ will never crash from this overflow, although I have seen it crash due to the playeringame overflow once. That interceptsoverflow.wad you demonstrated at the beginning easily crashes vanilla due to how many things and linedefs are placed in a row. I'm not sure what the exact minimum number is, but it eventually gets to a point where the game will immediately crash and leave an error message at the DOS prompt (or the game will freeze and you'll have to reboot DOS or close DOSBox :D). I've personally seen two messages with the first one being the most frequent ("P_CrossSubsector: ss %i with numss = %i" and "R_Subsector: ss %i with numss = %i"). Doomwiki states that these errors should never occur, but the error message article does note that various overflows may trigger messages like these. Sometimes, DOOM may completely freeze and DOSBox will crash occasionally. I haven't run any intentional intercepts overflow tests on any of my DOS machines yet, but I do plan to in the near future as DOSBox can be both more stable and less stable than a real DOS environment depending on the situation. I've experienced crashes that have happened sometime after the all-ghosts effect is triggered, but usually the game seems to die instantly if a crash is going to happen. I witnessed something very peculiar today while experimenting with the bug in vanilla using -solo-net (AKA using ipxsetup.exe and -nodes 1 instead of the modern source port parameter). I was adding additional corpses to a room by blowing myself up multiple times and after one of these deaths, I instantly blew up a second time when I respawned! The overflow had already been triggered at this point, but the player starts were still functional. I have no idea what happened, but I'll keep trying to replicate this and get a demo recording for someone to analyze (perhaps you'd like to check it out? :O) Anyway, I hope this information based on my own experience and experimentation is useful! I greatly appreciate this video and you were able to answer some questions I still had about this crazy bug. The main thing that confused me was demos with intercepts overflows that were seemingly triggered by far less intercepts than 128, so I'm really glad that mystery was solved! I assume that's why the overflow can happen on Black Tower and why I was unable to replicate it (I'll keep trying, though :D). Thanks again for this excellent addition to the analysis series and congratulations on 130k subscribers! P.S. I like the funny Pain Elementals at 6:46 and I see that my friend, Retro, was very pleased with them too :D
Thanks for your lengthy and interesting comment. If you don't mind you can DM me the demo file. Also the E1M8/E4M3/Black Tower all-ghosts footage was staged by manually setting the blockmap width to 0 as soon as I fired a shot. Those positions and angles will most likely not cause the bug normally.
Thanks for covering why the all ghosts effect can't be used to kill the IoS. You explained it pretty well when you responded to my previous comment asking if it was possible, but I still couldn't quite visualize it. So, anyways, thanks for crushing my hopes and dreams!
This just gave me an idea for a map where you can only shoot in specific spots or the bug will trigger. Probably not gonna make it tho since I'm a failure at making acceptable level design.
I'm gonna be honest, in all my years of being a novice I have never encountered this but that aside yes I highly enjoyed watching this my best to you and yours pal as always stay safe Doom guy.
Can I just say the sunlust music is fantastic for background ambience? I did not expect this subject from that thumbnail preview, the caco boo is adorable. Also this is probably your best thumbnail from the doom analysis videos in my opinion, very well made.
I love how Classic Doom is in still technically marvelous and fascinating, despite being archaic. Makes you respect how much work goes into making games. Think of all that goes on (sometimes) seamlessly in modern games. And look at Doom now! The amount of sheer calculations and potential interactions boggles the mind.
Videos like this are exactly why I like your channel. Deep, deep dives into the nooks and crannies of Doom's code... I wish more channels did stuff like this. I know there's that one guy who does Paper Mario videos like this, but beyond you two, I can't think of anyone else.
This has happened to me twice on the version I play on my switch. I thought the port was buggy! Thank you for explaining this Decino I never knew this!
Every time I watch this video, when you first name it "The Intercepts Overflow" I envision someone telling a scary campfire story, and I can just imagine the pause for effect right before "The Intercept Overflow". Brilliant, haha. Thank you for the DOOM analysis videos!
Thanks, Decino! I was really hoping to see the "crushed enemy resurrection" bug mentioned on your channel! I had no idea there was a separate ghost bug.
I now need to make a meme with like around 40 mr bones revenants and make some overused plutonia joke along the lines of "Welcome to the Casali Brother's Wild Ride - The Pain Never Ends!"
This leads to the very mysterious question: "Who asked?" Well, to understand the question, we have to understand the answer: So this very particular question is asking about who asked, the question is divided into two parts: Who & asked "Who" is what is called an "Interrogative word" which specifies the answer to make it suitable for the question, the "Who" here is specifying a person/human/homo sapiens/guy which has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human. Second: "asked" is a verb in the second condition of the forms of the verb, which are divided into three types: Regular, Past, or Past participle. and the verb "asked" is in the "Past" condition, which talks about the time that is gone and no longer exists. The original form of this particular verb is "ask", which is to say something in order to obtain an answer or some information. So, to summon what the answer wants from the previous two points, it's that: The answer wants to understand and know about the person/human/homo sapiens/guy who wanted to say something in order to obtain an answer or some information. So, in order to answer this question, we will have to identify two points: First: What was the question that the subject of the answer to the question "Who asked?" asked? Well, to understand this question, we will NOT have to understand what is the answer. We will just have to understand the definition of "Question" The "Question" is A sentence worded or expressed so as to elicit information. Questions could be identified using the "Interrogative Words", which we talked about earlier. these "Interrogative Words" are nine, which are: Who, What, Where, Why, Which, When, Whose, Whom, and How. We are going to explain each individually: As we said earlier: "Who" is specifying a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human. "What" is specifying a non-person/non-human/non-homo sapiens/non-guy who either does not have a brain that he can understand and think properly with, like plants, or objects, or they have a brain, either that their brains cannot understand and think properly, like animals, or their brain can understand and think properly, but their species/type is rather different from the society, like extraterrestrial creatures, so the answer should be as I said in the abstract: A(n) animal, plant, extraterrestrial creature, or object. "Where" is specifying a place, city, country, continent, etc. where something happens, or some(one/person/human/homo sapiens/guy), plant, animal, extraterrestrial creature or object which exists in a place, city, country, continent, etc. "Why" is specifying a reason for doing something. "Which" is specifying a choice of either two or more choices that the receiver of the question usually chooses. "When" is specifying a time in which either something already happened, or something will happen in either near, or far future, for example: "When will anyone save me as I was captured by MatPat for trying to comment a joke about his video?" "Whose" is specifying a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, and that person/human/homo sapiens/guy owns something, or someone ( if he is a human trafficker ), and the sender of the question is trying to find who owns that something, or someone. "Whom" is an old-fashioned term, not often used today. Many native English speakers are less than clear about its accurate use. In fact, the word serves the same purpose as "Who" questions, which as we said: specifies a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human, but tends to be used when it is the object of the verb. With modern English, there is no real need to use the term. "How" could be referring to the way something is done or refers to the status of the receiver of the question. Now, let's get back to where we were talking: Questions can be different, and many, and the possibility of guessing the question could be high or low according to the frequency of using it, but guessing a question which was asked for the first time is very difficult, so, it is not specific what was the question that the subject of the answer to the question "Who asked?" asked. Second: What is the purpose of the question "Who asked?"? Well, it could be referring to roasting someone as the humor of "No one asked.", and it could be referring to actually asking a question about who asked the question. So, here's the answer to the question "Who asked?": It could be anyone who made something unlikely for the others or someone who asked a question which could be a hint to treasure, or a last "sentence" from somebody, or something else. (s)He could be you. (s)He could be me. (s)He could be Elon Musk. (s)He could be even your mom. as long as they have made something unlikely for the others or they have asked a question which could be a hint to treasure, or a last "sentence" from somebody, or something else.
It's all fun and games until the demons decide to use idclip
Doomguy: Uses cheat codes
Demons: Understandable have a nice day
Demons: Uses cheat codes
Doomguy: Wait, that's illegal
This is 1 bug I always encounter: in the MS-DOS Doom1 E1M6 in the maze-like part, there's a zombieman who somehow appears outside te walls, forever haunting nobody. If that happens, you can't reach 100% kills without idspispopd.
Doomguy: Wait, this is Doom 2, so why is BFG Division playi-
Demon: *use idclip*
Doomguy: "You dare use my own spell against me, demon!"
and It's all fun and games till the demons decide to use iddqd
my favorite fact about this bug is that chocolate doom has a different memory layout (so it wouldn't work the same way), so instead, chocolate doom *manually* recreates the effect by overwriting the appropriate variables in the same order
Same with Prboom+.
OMG NO FUCKING WAY THAT THEY DID THAT'S SO COOL
Caco-Boo is a blessed creature I didn't know I needed in my life.
Feels like a Golden Souls enemy
Is it rule 34 immune?
@@raulsalcedo8332 dont give them ideas
@@raulsalcedo8332 The only thing that is given an exception to Rule 34 is if its a citation of Rule 34 also called Rule 35.
Otherwise no because it is something that is concieved making it exist so it is under Rule 34. (Unfortunately...)
This was a missed opportunity to call this video “whoops, all ghost”
As soon as I heard him call it the "all ghosts bug" I thought the same joke. :D
Good!
Never encountered this one in all my years of playing Doom. This is awesome, now I have to try and make it happen for giggles.
Keep in mind this only happens in Doom ports that:
1) Share similar memory addresses;
2) Don't fix ray cast rounding errors;
3) Don't fix the intercepts array overflowing.
PrBoom+ for example can only emulate the all-ghosts effect behaviour, but it doesn't actually directly overwrite memory through the intercepts array.
omg it's the funny madness man
Doom madness animation? 👀
Video was released 4 minutes ago, this comment is 20 hours ago, mmmkay
hmmm i see lol
I love how on the surface, Doom is "shoot it until it dies" but underneath there's a bunch of quirks like this. And then you have ASMR doom pumpkin man explaining it to you. Better than uni
It really reminds me of Super Mario 64 in that way, and Decino reminds me of PannenKoek2012.
I never made that connection before.
@@ImDemonAlchemist
I have never seen this awesome rare bug while ever playing this game. The block map bug however...
The block map bug is pain
I hate that it exists in Eternity and cannot be turned off in the compatibility options. Forgive me skillsaw, but I ain't completing Heartland until that happens.
@ASDF
I too use GZDoom to avoid the Blockmap Bug and I'm not even ashamed to admit it.
I haven't seen this since playing Doom on a 0486 years ago.*
*On regular vanilla maps.
why do i have this weird deja vu feeling?
Coming back after Zero Master used the insights from this video to get new world records in E1M8 and Plutonia map 11. Congratulations, decino! You deserve a Nobel prize in Doom science.
Very cool this video inspired a new speed run tactic
9:20 so how does Zero Master do it reliably enough to use?
OK I see his explanation in the description of his video. Basically his brute force method was using inputs that he could replicate without TAS. Still I wonder how precise do the inputs have to be?
His video:
th-cam.com/video/P01d-AmqByU/w-d-xo.html
@@YogiTheBearMan Karl Jobst has covered Zero Master's technique here:
th-cam.com/video/T_5ZYJBgQyM/w-d-xo.html
He explains that Zero Master's simulations performed about 300 years of gameplay to find the solution. Great video.
@@Drahcir_XIII still doesn't explain how he went from discovering a random string of inputs that happened to activate the glitch to implementing it in an rta run, like did he figure out a way to do it consistently and if so how
@@aclonymousthe video does explain it. The 300 years of game simulated was used to run a simple string of inputs constantly to try and find the values for the bug to happen.
Basically the simulation did the inputs than ran into a wall, if it ran into the wall, it would reset. it kept on doing that until it went through the wall
the inputs given were simple. Would have been something like, move forward 20 map units, shoot 3 times, turn to the right, shoot again and then go into the wall.
Because they were simple enough inputs that a person could do it, ZeroMaster just replicated the inputs
6:37 That is one horrifiying image. The endless maw of hell's demons just trying to shake their way through matter... It's so unsettling.
Oh you want to know what i see
Hehe cocademons squeeze line
0:16 seems much more frightening, due to the fact that nothing is stopping them, and there's eerie music playing.
@@lugbzurg8987 Playing Another World of Beasts/Esper World was a good choice.
"The only way to exit the level is through a death exit damaging floor."
Dude, that is obscure as hell. You're amazing at analyzing the Doom engine and pushing it to its limits. I don't think anyone has ever gone this far and this deep. I always get happy when you release a new video like this.
Well i mean doom's ray tracing only takes into account anything on the x or y axis since those are the only two axes you can aim and shoot on that have anything to intercept your bullets with so it's kind of obvious why pools and damaging floors can still hurt doomguy,
Still obscure as hell. Everything in this video is.
I love that, despite Doom being a game older than a significant part of TH-cam's overall userbase, you've still managed to build an entire channel primarily on the game's myriad quirks.
Also, at 10:01, is that Mr. Bones' Wild Ride on the right? Nice subtle nod to another legendary old game.
The series is still getting new releases, and I think they even put at least one of the old ones in Eternal; there's the Unity port for everyone on console as well, and it's dirt-cheap (5 bucks for each game, and it goes on sale sometimes), and it's shaped up to be a very respectable source port (as opposed to the disaster it launched as) and even include a bunch of prominent WADs as well. Doom is arguably more accessible now than it's been since its heyday, even the most tech-illiterate person can just buy it, download and play.
@@hoodedman6579 Yep! When I heard doom eternal was coming out, I bought doom 2016, and after that decided to play through doom 1 and 2 before it released. I had _heard_ of doom before, but had never sat down and played it. I'm now a big doom fan even working on a custom 7 map wad, and after that's done I'm going to give final doom a go.
@@kingkuma4112 Nice! That's quite the dedicated fan you've become! Is there a place I can follow your progress on your wad, perhaps? Maybe reply to this comment chain when it's done?
@@E5rael Yeah, I can do it.
Lol, it does actually look like it IS Mr. Bones' Wild Ride, superimposed on a revenant.
The scariest thing here aren’t the ghosts, not able to complete levels, or even this ruining a speed run.
It was the code.
I remember seeing this exact bug in one of Altimamantoid's outtakes with TNT Map 22 ten years ago. It happened right in the middle of his rant about awful the map was and it killed him within seconds.
Clearly the map didn't like being badmouthed and got revenge.
Well that and it was a community map that was never meant to be bought so having TNT Evilution's quality go south in the middle towards the end of the megawad would have been fine if it was released for free like it was planned to. Honestly i would have been fine with just the plutonia experiment as final doom.
@@michealpersicko9531 For the most part, I enjoyed TNT Evilution. Most of the levels are creative and interesting, and pushed the engine in various directions. Also, it's not like the original doom2.wad was the greatest thing either. No one had yet truely mastered the art of Doom map making, the tools at the time were poor, and computers couldn't handle anything beyond simple map geometry with only a handful of enemies onscreen at a time.
Now, I personally dislike Plutonia. It seems to love putting hitscan enemies and archviles in places that are very awkward to aim into or hidden, so that you take a bunch of unavoidable damage if you don't have the proper approaches memorized, and has too many combat arenas where movement is downright awkward. Also, the architecture is, with a few exceptions, rather bland and repetative. Where in TNT you never know what sights you'll see around the next corner, with Plutonia it will surely be more brown walls with green vines and chaingunners.
I've played through all of TNT twice. With Plutonia, I started two or three times, but never got past the second or third level before getting bored and annoyed and dropping it.
@@michealpersicko9531 Plutonia and Evilution are a perfect pair -- for people like me who hate Plutonia's high-difficulty, short-length maps and prefer to actually spend time exploring without running like a blue-assed fly from revenant missiles. Either one alone would leave a chunk of players disappointed.
decino: your position and angle need to be absolutely dead on
Zero Master: challenge accepted
"Deep into the code" would have been perfect for this. Excellent work and explanation !
Knee Deep In The Code
@@mjc0961
The Shores of Code
In-Code
Thy Code Consumed
Sign(Sigil)
And finally:
*Tech Gone Bad*
@@mjc0961 Yep, there we go. That's brilliant. ♥
Codemonium
The ancient code
looks like you guys getting so close getting those last secrets in e4-3 and icon of sin pacifist! maybe one day...
It had a really missed opportunity to be called “the specter bug”
Cause thats a ghostly named enemy
Nothing to do with partial invisibility tho.
i think when it was named, specters didn't exist in doom so i don't think it was an idea to come up with
@@YourTypicalWarp so it was named before the game came out
@@YourTypicalWarp No idea why this comment has any likes, that's so untrue. Spectres have always existed in Doom. No idea where you got the idea that this insanely rare bug that likely wasn't discovered until some time after Doom II or even Final Doom released -- would be named as a "ghost" bug because spectres didn't exist... It's because you literally act like a ghost. You can go through walls and are barely able to have any interactions at all.
Spectres can interact with the environment... and attack.. and be hit. So what way is this remotely similar to how Spectres function....?
The weird bullshit some of you guys say is insane.
whoa, look, i was just misunderstood, i thought he was talking about the spirits from doom eternal :\ now, instead of starting an insanely dumb argument, i misunderstood the enemy and i apologize!
Glad Karl pointed me towards this video and your channel. Super cool videos! Just insane that your video about this glitch, and your breakdown was eventually used to actually find a practical use for this bug, and used to break another Doom speed run! Leave it to you crazy talented maniacs to find out how this all works, and how to exploit and activate these glitches, even if it takes years to do so!
Congrats to you all!
Me like 45 minutes ago: "Huh, there hasn't been a decino video in a few weeks now..."
Me, just now, opening youtube again: "Decino video uploaded 34 minutes ago"
impressive
"Hmmm, decino hasn't posted a video in a while, I hope he's ok."
"Y'know, he's probably fine, just working on a yellow video"
-me for the last 2 weeks
Good to see you're still with us and not a spooky ghost lol
....I guess you just got a deci-boo
@@johndexterzarate6663 he posted on a community team that he was out of town and busy on a new video some time before this video
That squish sound at 0:03 is hilarious:)
Apparently this glitch also happens when trying to load a massive map, but it happens differently depending on the source port. GZDoom does turn enemies into ghosts, but vanilla compatible ports make the monsters solid but invincible.
Really weird
@@theraymunator Sourceports may emulate the all ghosts effect in some way or another. Vanilla compatible sourceports will behave very similarly to original game in such event, where intercept array starts overwriting unrelated memory.
All it takes is for the hitscan shot to go through a lot of targets.
I remember having nightmares as a kid like this, being stuck in Doom but the monsters were unkillable.
Did they also chase you out of bounds when you tried to use noclip or freeze?
s p o k i
5:22 ZeroMaster "Hmmmm, interesting..."
Damn, never faced this bug, rather cool.
And what a surprise the Sandy's map was used for the reference (in Civvie11's voice)
#freecivvie
The Legends are coming!
5:28
Damn that’s a cool way of getting around that, looking forward to maybe seeing it as another “practically possible” addition in “Doom Challenges Deemed Impossible Update Update”
Decino hearting comments a year later. What a legend. P.S. His Serious Sam videos are goated, specifically the 100% playthroughs.
It's like this is a glimpse of the true form of noclip, where not even projectiles can interact with you... I love how much effort you put into these obscure quirks and trivia from a game that seemingly has risen in popularity once more after decades of being extremely niched. Thank you ducino, and cheers!
Funnily enough, before there was research done into why this bug happens, it was known to deathmatch players as something along the lines of "the DM noclip bug", because if there's no monsters around it just looks like everyone turned on noclip at the same time.
Ducino
@@LonelySpaceDetective But even that is kind of a misnomer, because noclip doesn't prevent you from flipping switches and it doesn't stop your projectiles from colliding too.
Here from Karl, but it's not my first time. I've seen these videos so many times by now, Karl just gave me another reason to watch them again.
When the Skeleton turns into a Ghost: _wait that's illegal_
Sans: Hold my beer
But what if Doom had a Ghost enemy, does that mean the Ghost turns into a Ghost?
@@CheddarCheeseRebirthed yeah, *This is Big Brain time*
@@reffo5548 GHOST GHOST
We're reaching levels of 2spoopy4me that shouldn't even be possible!
Decino to his therapist: "Demon ghosts are not _corporeal_ and they can hurt me if I get close!"
This leads to the very mysterious question: "Who asked?" Well, to understand the question, we have to understand the answer: So this very particular question is asking about who asked, the question is divided into two parts: Who & asked "Who" is what is called an "Interrogative word" which specifies the answer to make it suitable for the question, the "Who" here is specifying a person/human/homo sapiens/guy which has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human. Second: "asked" is a verb in the second condition of the forms of the verb, which are divided into three types: Regular, Past, or Past participle. and the verb "asked" is in the "Past" condition, which talks about the time that is gone and no longer exists. The original form of this particular verb is "ask", which is to say something in order to obtain an answer or some information. So, to summon what the answer wants from the previous two points, it's that: The answer wants to understand and know about the person/human/homo sapiens/guy who wanted to say something in order to obtain an answer or some information. So, in order to answer this question, we will have to identify two points: First: What was the question that the subject of the answer to the question "Who asked?" asked? Well, to understand this question, we will NOT have to understand what is the answer. We will just have to understand the definition of "Question" The "Question" is A sentence worded or expressed so as to elicit information. Questions could be identified using the "Interrogative Words", which we talked about earlier. these "Interrogative Words" are nine, which are: Who, What, Where, Why, Which, When, Whose, Whom, and How. We are going to explain each individually: As we said earlier: "Who" is specifying a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human. "What" is specifying a non-person/non-human/non-homo sapiens/non-guy who either does not have a brain that he can understand and think properly with, like plants, or objects, or they have a brain, either that their brains cannot understand and think properly, like animals, or their brain can understand and think properly, but their species/type is rather different from the society, like extraterrestrial creatures, so the answer should be as I said in the abstract: A(n) animal, plant, extraterrestrial creature, or object. "Where" is specifying a place, city, country, continent, etc. where something happens, or some(one/person/human/homo sapiens/guy), plant, animal, extraterrestrial creature or object which exists in a place, city, country, continent, etc. "Why" is specifying a reason for doing something. "Which" is specifying a choice of either two or more choices that the receiver of the question usually chooses. "When" is specifying a time in which either something already happened, or something will happen in either near, or far future, for example: "When will anyone save me as I was captured by MatPat for trying to comment a joke about his video?" "Whose" is specifying a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, and that person/human/homo sapiens/guy owns something, or someone ( if he is a human trafficker ), and the sender of the question is trying to find who owns that something, or someone. "Whom" is an old-fashioned term, not often used today. Many native English speakers are less than clear about its accurate use. In fact, the word serves the same purpose as "Who" questions, which as we said: specifies a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human, but tends to be used when it is the object of the verb. With modern English, there is no real need to use the term. "How" could be referring to the way something is done or refers to the status of the receiver of the question. Now, let's get back to where we were talking: Questions can be different, and many, and the possibility of guessing the question could be high or low according to the frequency of using it, but guessing a question which was asked for the first time is very difficult, so, it is not specific what was the question that the subject of the answer to the question "Who asked?" asked. Second: What is the purpose of the question "Who asked?"? Well, it could be referring to roasting someone as the humor of "No one asked.", and it could be referring to actually asking a question about who asked the question. So, here's the answer to the question "Who asked?": It could be anyone who made something unlikely for the others or someone who asked a question which could be a hint to treasure, or a last "sentence" from somebody, or something else. (s)He could be you. (s)He could be me. (s)He could be Elon Musk. (s)He could be even your mom. as long as they have made something unlikely for the others or they have asked a question which could be a hint to treasure, or a last "sentence" from somebody, or something else.
I've played the classic doom games since they came out. Never have I managed to see this bug happen. This is why I enjoy this channel, it shows how much there still is to find in old Doom
So i tried that yesterday (6:07)
But sadly the game crashes (on ps4) when the kill count is over 1610+
i even got a save and once i move.....Crash!
So you can't do the all ghosts effect on the Unity port on Doom II's MAP30. (4:10)
If i did it... It would be even scarier than normal doom 2 revenants
WHEN I SEE THAT YELLOW BACKGROUND UPLOAD I GET SO EXCITED
Me too.
I saw Karl's video and was like "wait, I could have sworn I had seen a video on this before..." then Karl directly quoted this video and I was like "oh right, that was where!"
4:12 Gotta love that Sunlust music!
Glad I can be of service :)
Glad you’re back, this was probably one of the most interesting analysis videos
Seeing Karl recommending decino put a smile on my face and warmed my heart!
I had specific memories of causing this bug when I was a kid, on Doom 2 map 30.
Now I know why.
Missed opportunity to call it the "Oops! All Ghosts!" effect.
Hello you absolute Legends. ZeroMaster shows us why he's the greatest speedrunner in Doom history yet again.
This video is ground-breaking. The 128+ things intercepts overflow isn't a mystery to many people, but what you explained at 7:00 was outright fascinating, it is new knowledge for me, and I believe for the community as a whole too. I've been wondering about this for so long... I never thought I'd see a fixed-point-value precision error having such massive consequences.
But I disagree with you: I believe that, in light of this information, the speedrunning community might be able to use this to trigger the bug on demand, even on maps where there aren't 128+ things in a line. How? First, you can use a corner + take as-small-as-possible steps (single-tic moves) from that corner to get to a fixed position. Second, with shorttics you can easily and consistently turn to a fixed angle. So from this day forwards, discovering setups to trigger the all-ghosts bug on demand is much more feasible.
What will the speedrunning community achieve with this? No idea, but I can't wait to find out! :)
As always, amazing stuff decino!
Thanks Coin, that means a lot to me. I may have done it wrong (and didn't spend much time on it honestly), but every time I hugged a corner the fractional values would differ slightly. We were already discussing on Discord to write a program or simulation that brute forces a bunch of precise coordinates and angles to see where you can overflow the intercepts on demand. Useful for TAS demos for sure.
My man finally got the recognition he deserves
Karl Jobst video led me here. Great video !
The way it moves the offset past where it should be is similar to items over 99 in gen1 pokemon.
The gameboy has two sets of tilemaps that overlap. At the end of the overlapping parts are the numbers for the interface. So if you have 100 of something, the "10" is just the tile directly after the tile for "9", which is part of the map you're walking in. And the missingno glitch increases the item in the 6th slot of your inventory by 128, moving it past 99 into the map geometry.
But no ghost mode there, it's just a pure interface issue, the system can handle item counts up to 255 without issue. Since 99 + 128 is less than 255, you will never run into a size that would cause issues.
So while the utility of both are different, both work in a similar way, moving data into areas where they shouldn't be.
it's very interesting how a simple rounding error can have such a strange effect. i'm here from karl's video
My country usually have a proverb saying Demons let go, ghosts catch you.
In DOOM this exists too?
Which country?
@@fordunfocus VietNam country because my name is over there.
@@vietnamgaminghm does Vietnam need the N to be capitalised?
@@TheDoomer666 If you are spelling the name in English it will only be Vietnam without space between
However the Vietnamese writes it as Việt Nam or Viet Nam with space between
In Vietnamese, names such as of humans, animals and countries are written with capitalized at the start of each syllable:
America=Hoa Ki or My/Mi
China=Trung Quoc based on the Chinese spelling Zhongguo
Korea=Han Quoc(Hanguk) and Trieu Tien(Chosun)...
@@vietnamgaminghm whoa bro, did you just revisit this video randomly? or are you responding to every notification after coming back from the dead lol
thanks for the explanation tho! 👍
Ive been paying doom for over 15 years, never in my live heard of this, marvelous how Decino never stops surprising me with new things every video. Amazing
The actual reason it happens in Map 21 is because Nirvana just sucks that hard.
yep
I'm sorry to inform you, sir, but there's at least one person on Earth who likes Map21...
... and he's in this thread right now.
@@MrCantStopTheRobot FUCK FUCK ITS NOT ME ITS NOT ME I SWEAR ITS IRONIC I SWEAR I ONLY LIKE IT IRONICALLY
@@MrCantStopTheRobot we must take their legs off
@@kingwaffleton1774 alright, hand me the chainsaw, and we'll start the investigation...
here from Karl, was not dissapointed!
The fact that there's a way to trigger the candle secrets in Sever the Wicked is so cool
The gig is up.
Karl Jobst sent us.
Nice, you got a shoutout from Karl Jobst
When I was a kid I used to accidentally trigger this bug on Plutonia's MAP30 by waking up the Icon, turning on god mode, and then seeing if I could fill up the entire map with monster bodies. After a while of doing this they started noclipping and I couldn't kill them. I always just assumed I overloaded the game with too many enemies.
Yeah, I ran into this bug the same way back in the day (though in my case it was on Doom 2's MAP30). As much as I like understanding how and why it happens, it still takes some of the magic out of it. :P
I love seeing the influx of people to your channel Pumpkin Man, you are a true absolute legend!
I actually encountered this for the first time quite recently... just a few months ago while playing through TNT Evilutuion in Map 09: Stronghold. At the time I had no idea what it was, and assumed I'd triggered the void glitch somehow by accident (i.e. the one speedrunners use in Doom 1's Halls of the Damned to get to the exit). But now that I've seen this, and given the large enemy count for that map (at least by 1996 commercial Doom IWAD standards), now it makes sense how I triggered this bug. If anyone wants to mess around with that map... I think(?) I was in the southwest portion of the map, but like I said, it's been a few months now, so I could be remembering wrong.
Decino, a Doomtuber who teaches us rare bugs that I'd never see.
This leads to the very mysterious question: "Who asked?" Well, to understand the question, we have to understand the answer: So this very particular question is asking about who asked, the question is divided into two parts: Who & asked "Who" is what is called an "Interrogative word" which specifies the answer to make it suitable for the question, the "Who" here is specifying a person/human/homo sapiens/guy which has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human. Second: "asked" is a verb in the second condition of the forms of the verb, which are divided into three types: Regular, Past, or Past participle. and the verb "asked" is in the "Past" condition, which talks about the time that is gone and no longer exists. The original form of this particular verb is "ask", which is to say something in order to obtain an answer or some information. So, to summon what the answer wants from the previous two points, it's that: The answer wants to understand and know about the person/human/homo sapiens/guy who wanted to say something in order to obtain an answer or some information. So, in order to answer this question, we will have to identify two points: First: What was the question that the subject of the answer to the question "Who asked?" asked? Well, to understand this question, we will NOT have to understand what is the answer. We will just have to understand the definition of "Question" The "Question" is A sentence worded or expressed so as to elicit information. Questions could be identified using the "Interrogative Words", which we talked about earlier. these "Interrogative Words" are nine, which are: Who, What, Where, Why, Which, When, Whose, Whom, and How. We are going to explain each individually: As we said earlier: "Who" is specifying a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human. "What" is specifying a non-person/non-human/non-homo sapiens/non-guy who either does not have a brain that he can understand and think properly with, like plants, or objects, or they have a brain, either that their brains cannot understand and think properly, like animals, or their brain can understand and think properly, but their species/type is rather different from the society, like extraterrestrial creatures, so the answer should be as I said in the abstract: A(n) animal, plant, extraterrestrial creature, or object. "Where" is specifying a place, city, country, continent, etc. where something happens, or some(one/person/human/homo sapiens/guy), plant, animal, extraterrestrial creature or object which exists in a place, city, country, continent, etc. "Why" is specifying a reason for doing something. "Which" is specifying a choice of either two or more choices that the receiver of the question usually chooses. "When" is specifying a time in which either something already happened, or something will happen in either near, or far future, for example: "When will anyone save me as I was captured by MatPat for trying to comment a joke about his video?" "Whose" is specifying a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, and that person/human/homo sapiens/guy owns something, or someone ( if he is a human trafficker ), and the sender of the question is trying to find who owns that something, or someone. "Whom" is an old-fashioned term, not often used today. Many native English speakers are less than clear about its accurate use. In fact, the word serves the same purpose as "Who" questions, which as we said: specifies a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human, but tends to be used when it is the object of the verb. With modern English, there is no real need to use the term. "How" could be referring to the way something is done or refers to the status of the receiver of the question. Now, let's get back to where we were talking: Questions can be different, and many, and the possibility of guessing the question could be high or low according to the frequency of using it, but guessing a question which was asked for the first time is very difficult, so, it is not specific what was the question that the subject of the answer to the question "Who asked?" asked. Second: What is the purpose of the question "Who asked?"? Well, it could be referring to roasting someone as the humor of "No one asked.", and it could be referring to actually asking a question about who asked the question. So, here's the answer to the question "Who asked?": It could be anyone who made something unlikely for the others or someone who asked a question which could be a hint to treasure, or a last "sentence" from somebody, or something else. (s)He could be you. (s)He could be me. (s)He could be Elon Musk. (s)He could be even your mom. as long as they have made something unlikely for the others or they have asked a question which could be a hint to treasure, or a last "sentence" from somebody, or something else.
As a fledgling programmer, learning about dooms code is so educational and entertaining
I feel most alive when rapidly approaching decino's new video.
Learned something new today. These series on how the doom code work are really interesting. I'd love to see some breakdowns for more contemporary engines.
This leads to the very mysterious question: "Who asked?" Well, to understand the question, we have to understand the answer: So this very particular question is asking about who asked, the question is divided into two parts: Who & asked "Who" is what is called an "Interrogative word" which specifies the answer to make it suitable for the question, the "Who" here is specifying a person/human/homo sapiens/guy which has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human. Second: "asked" is a verb in the second condition of the forms of the verb, which are divided into three types: Regular, Past, or Past participle. and the verb "asked" is in the "Past" condition, which talks about the time that is gone and no longer exists. The original form of this particular verb is "ask", which is to say something in order to obtain an answer or some information. So, to summon what the answer wants from the previous two points, it's that: The answer wants to understand and know about the person/human/homo sapiens/guy who wanted to say something in order to obtain an answer or some information. So, in order to answer this question, we will have to identify two points: First: What was the question that the subject of the answer to the question "Who asked?" asked? Well, to understand this question, we will NOT have to understand what is the answer. We will just have to understand the definition of "Question" The "Question" is A sentence worded or expressed so as to elicit information. Questions could be identified using the "Interrogative Words", which we talked about earlier. these "Interrogative Words" are nine, which are: Who, What, Where, Why, Which, When, Whose, Whom, and How. We are going to explain each individually: As we said earlier: "Who" is specifying a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human. "What" is specifying a non-person/non-human/non-homo sapiens/non-guy who either does not have a brain that he can understand and think properly with, like plants, or objects, or they have a brain, either that their brains cannot understand and think properly, like animals, or their brain can understand and think properly, but their species/type is rather different from the society, like extraterrestrial creatures, so the answer should be as I said in the abstract: A(n) animal, plant, extraterrestrial creature, or object. "Where" is specifying a place, city, country, continent, etc. where something happens, or some(one/person/human/homo sapiens/guy), plant, animal, extraterrestrial creature or object which exists in a place, city, country, continent, etc. "Why" is specifying a reason for doing something. "Which" is specifying a choice of either two or more choices that the receiver of the question usually chooses. "When" is specifying a time in which either something already happened, or something will happen in either near, or far future, for example: "When will anyone save me as I was captured by MatPat for trying to comment a joke about his video?" "Whose" is specifying a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, and that person/human/homo sapiens/guy owns something, or someone ( if he is a human trafficker ), and the sender of the question is trying to find who owns that something, or someone. "Whom" is an old-fashioned term, not often used today. Many native English speakers are less than clear about its accurate use. In fact, the word serves the same purpose as "Who" questions, which as we said: specifies a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human, but tends to be used when it is the object of the verb. With modern English, there is no real need to use the term. "How" could be referring to the way something is done or refers to the status of the receiver of the question. Now, let's get back to where we were talking: Questions can be different, and many, and the possibility of guessing the question could be high or low according to the frequency of using it, but guessing a question which was asked for the first time is very difficult, so, it is not specific what was the question that the subject of the answer to the question "Who asked?" asked. Second: What is the purpose of the question "Who asked?"? Well, it could be referring to roasting someone as the humor of "No one asked.", and it could be referring to actually asking a question about who asked the question. So, here's the answer to the question "Who asked?": It could be anyone who made something unlikely for the others or someone who asked a question which could be a hint to treasure, or a last "sentence" from somebody, or something else. (s)He could be you. (s)He could be me. (s)He could be Elon Musk. (s)He could be even your mom. as long as they have made something unlikely for the others or they have asked a question which could be a hint to treasure, or a last "sentence" from somebody, or something else.
An Absolute Legend sent me here.
Watched this amazing video like 10 times now. Karl Jobst - the legend, brought me back again. Nice shout out from him to our hero decino!
Encountered this bug before, when I made a map with 999 revenants.
You monster
That’s crazy.
Marphy is that you?
the skelotons got angry and became ghost skeolotons
@@yawg691 A monster you say? No... I'm a god!
I encountered this bug once as a kid. I don't remember which map it was but I remember never wanting to play that map again because of how creepy it was. It makes me wonder what kind of interesting things you can do with this bug that haven't been discovered yet
Bad luck? Speedrunners would like to disagree with that, they'll find a way just like life xD
Always to see Decino's analysis, it could be entertaining and educating at same time
Wana get good at doom?: Watch a video with a funny yellow color.
Wana know how to code?: Watch a video with a funny yellow color
Wana know how was doom created?: Watch a video with a funny yellow color
Wana know how graphics were made for doom?: Watch a video with a funny yellow color.
Wana know how were SFX things made for doom?: Watch a video with a funny yellow color.
Wana know how weapons work in doom?: Watch a video with a funny yellow color
Wana know how powerups work in doom?: Watch a video with a funny yellow color
Wana know how armor works in doom?:Watch a video with a funny yellow color.
Need demon tierlists for doom?: Watch a video with a funny yellow color.
Wana know enemy stats for doom?: Watch a video with a funny yellow color
Wana know seroius sam stuff?: Watch a video with a funny yellow color.
Wana know how shield suits work in doom?: Wana get good at doom?: Watch a video with a funny yellow color.
Wana know how to code?: Watch a video with a funny yellow color
Wana know how was doom created?: Watch a video with a funny yellow color
Wana know how graphics were made for doom?: Watch a video with a funny yellow color.
Wana know how were SFX things made for doom?: Watch a video with a funny yellow color.
Wana know how weapons work in doom?: Watch a video with a funny yellow color
Wana know how powerups work in doom?: Watch a video with a funny yellow color
Wana know how armor works in doom?:Watch a video with a funny yellow color.
Need demon tierlists for soom?: Watch a video with a funny yellow color.
Wana know enemy stats for doom?: Watch a video with a funny yellow color
Wana know seroius sam stuff?: Watch a video with a funny yellow color.
Wana see if pacifist runs and chalanges are possible in doom?: Wana get good at doom?: Watch a video with a funny yellow color.
Wana know how to code?: Watch a video with a funny yellow color
Wana know how was doom created?: Watch a video with a funny yellow color
Wana know how graphics were made for doom?: Watch a video with a funny yellow color.
Wana know how were SFX things made for doom?: Watch a video with a funny yellow color.
Wana know how weapons work in doom?: Watch a video with a funny yellow color
Wana know how powerups work in doom?: Watch a video with a funny yellow color
Wana know how armor works in doom?:Watch a video with a funny yellow color.
Need demon tierlists for soom?: Watch a video with a funny yellow color.
Wana know enemy stats for doom?: Watch a video with a funny yellow color
Wana know seroius sam stuff?: Watch a video with a funny yellow color.
thanks decino, as a software engineer its awesome hearing the detailed explanation of these bugs, nothing like a good old array index out of bounds / overflow
Doomguy just decided to open a box of "Oops! All ghosts!" cereal
Huge thanks for this informative video! I feel like it might not get as many views as your other analysis videos, but boy, was it a real treat to watch. Looking forward to more coverage of obscure bugs!
Here again, from Karl Jobst
same
Decino, I was furloughed for basically all of 2020 and I found your channel at the beginning of quarantine right after I beat DOOM, 2, 64, and 2016. I love watching all your videos and your play series, especially when you tried DOOM 64. I started working a new job in February and I have missed so many videos unfortunately. I just opened TH-cam and I saw the yellow background for this video and got so excited; I felt like I was pulled back to 2020 for a second in a good way. I just wanted to get weirdly sentimental and say thank you for keeping me sane through that crazy year :)
Karl brought me back here today and i'm nerding out with the numbers (and my half a physics degree lol), the 9 significant figures required to recreate the effect you describe at 9:19 i mean, it's literally more accurate that the B I G announcements that the large hadron collider has made over the past decade (six sigma is regarded as HUGE STATISTICALLY RELEVANT NEWS with 8 sig fig)
Loving the ghostly imagery. The ride never ends with decino
I appreciate Mr Bone's Wild Ride in the thumbnail.
I've been playing Doom since its release. Today (2024-09-24), for the first time ever, I encountered the ghost bug on a Sunder map. Fun fact: it took me a while to realize it was the ghost bug because there were sooo many monsters in just a very big room. I was at a stage where Revenants were on an upper platform with no way to come down. Suddenly, I saw them right in front of me and thought, 'How the hell did you guys get down here?' That’s when I finally realized it was the ghost bug, FINALLY after 30 years 😅
Always good to see another video from you decino. Also grats on 130k, I'm looking forward to whenever the next Sunder stream will be as you got some amazing levels coming up.
Also I recommend anyone who enjoys decino's doom wad playthroughs, especially the difficult ones, to subscribe to A1s(the link in this video description) as his content is fairly similar.
I encountered an invincible Shotgunner while playing Co-op in the DOOM + DOOM II port, It was "The Express Elevator to Hell" in the Master Levels.
Now, watching this video, it seems like it was the Arch-vile Resurrect Glitch. That was very fun to encounter at the end of that map.
Thank you so much for making this analysis video, decino! I had mentioned to you previously that I was pretty familiar with the intercepts overflow, but I still didn't know all the specifics regarding things like how many intercepts were needed to cause the all-ghosts effect. I've encountered the overflow dozens of times in the past few months (not including intentionally triggering it) and I've seen it cause different issues at times. Perhaps the following info will be useful to you and also explain what happens when too many intercepts occur (some people were asking about that in the comments and I have the answer :D).
On one of my own maps, the overflow was very easy to trigger (too many linedefs for extra lighting variation). However, it seemed to be incredibly minor and I was unable to notice any issues with gameplay. The only reason I knew it occurred was thanks to PrBoom+'s optional warning message (very handy for playtests!). The player starts could get messed up in cooperative if a few player corpses were lined up with the ceiling lights. I fixed this as soon as I discovered it on that map by reducing the amount of lighting variation slightly :D
The epic slaughtermap, Heck on Earth (the one I mentioned with the ghost funnies :D), from my upcoming megawad does have a small chance for the all-ghosts effect. It's situational as it'll require a lot of monster corpses to be lined up, but with 1,080 monsters that's definitely not too difficult. The map gives the monsters plenty of room to move around so this should be very rare and I have tweaked it to help reduce the chance (I also playtest my maps 100+ times for quality assurance :D). Before tweaking it, I encountered the overflow again, but this time it seemed to make collision less precise, although the map was still playable. I mean, 7 SSG shots to kill an Arachnotron when you're right up in his face is definitely not just bad RNG and the blockmap bug :D
The intercepts overflow is guaranteed to crash vanilla DOOM if there are too many additional intercepts. As far as I know, PrBoom+ will never crash from this overflow, although I have seen it crash due to the playeringame overflow once. That interceptsoverflow.wad you demonstrated at the beginning easily crashes vanilla due to how many things and linedefs are placed in a row. I'm not sure what the exact minimum number is, but it eventually gets to a point where the game will immediately crash and leave an error message at the DOS prompt (or the game will freeze and you'll have to reboot DOS or close DOSBox :D). I've personally seen two messages with the first one being the most frequent ("P_CrossSubsector: ss %i with numss = %i" and "R_Subsector: ss %i with numss = %i"). Doomwiki states that these errors should never occur, but the error message article does note that various overflows may trigger messages like these.
Sometimes, DOOM may completely freeze and DOSBox will crash occasionally. I haven't run any intentional intercepts overflow tests on any of my DOS machines yet, but I do plan to in the near future as DOSBox can be both more stable and less stable than a real DOS environment depending on the situation. I've experienced crashes that have happened sometime after the all-ghosts effect is triggered, but usually the game seems to die instantly if a crash is going to happen.
I witnessed something very peculiar today while experimenting with the bug in vanilla using -solo-net (AKA using ipxsetup.exe and -nodes 1 instead of the modern source port parameter). I was adding additional corpses to a room by blowing myself up multiple times and after one of these deaths, I instantly blew up a second time when I respawned! The overflow had already been triggered at this point, but the player starts were still functional. I have no idea what happened, but I'll keep trying to replicate this and get a demo recording for someone to analyze (perhaps you'd like to check it out? :O)
Anyway, I hope this information based on my own experience and experimentation is useful! I greatly appreciate this video and you were able to answer some questions I still had about this crazy bug. The main thing that confused me was demos with intercepts overflows that were seemingly triggered by far less intercepts than 128, so I'm really glad that mystery was solved! I assume that's why the overflow can happen on Black Tower and why I was unable to replicate it (I'll keep trying, though :D). Thanks again for this excellent addition to the analysis series and congratulations on 130k subscribers!
P.S. I like the funny Pain Elementals at 6:46 and I see that my friend, Retro, was very pleased with them too :D
Thanks for your lengthy and interesting comment. If you don't mind you can DM me the demo file. Also the E1M8/E4M3/Black Tower all-ghosts footage was staged by manually setting the blockmap width to 0 as soon as I fired a shot. Those positions and angles will most likely not cause the bug normally.
Thanks for covering why the all ghosts effect can't be used to kill the IoS. You explained it pretty well when you responded to my previous comment asking if it was possible, but I still couldn't quite visualize it.
So, anyways, thanks for crushing my hopes and dreams!
This just gave me an idea for a map where you can only shoot in specific spots or the bug will trigger. Probably not gonna make it tho since I'm a failure at making acceptable level design.
how do u make levels
Decino: I have a feeling there's more to discover.
ZeroMaster: I smell a new world record.
As a programmer, if you're short on bugs just ask people to implement any kind of geometry routine
A friend of mine streamed his first UV Fast clear and the squash-resurrect ghost bug occurred _twice_ on him, was an interesting sight
I'm gonna be honest, in all my years of being a novice I have never encountered this but that aside yes I highly enjoyed watching this my best to you and yours pal as always stay safe Doom guy.
Can I just say the sunlust music is fantastic for background ambience? I did not expect this subject from that thumbnail preview, the caco boo is adorable. Also this is probably your best thumbnail from the doom analysis videos in my opinion, very well made.
3:47 whatever is in the background genuinely startled me
It's very dark, slowed down and blurry Back to Saturn X footage.
@@decino I see, it kinda looked like a red hand that was suddenly reaching for the screen (at least that's how my eyes interpreted it)
I love how Classic Doom is in still technically marvelous and fascinating, despite being archaic.
Makes you respect how much work goes into making games.
Think of all that goes on (sometimes) seamlessly in modern games.
And look at Doom now!
The amount of sheer calculations and potential interactions boggles the mind.
Ghosts? Is that what you meant with "ded"? :)
Anyway, good to have you back.
Videos like this are exactly why I like your channel. Deep, deep dives into the nooks and crannies of Doom's code... I wish more channels did stuff like this. I know there's that one guy who does Paper Mario videos like this, but beyond you two, I can't think of anyone else.
3:11 mmmmm bmaporgy
I like TH-cam channels like this that dedicate it's time for a specific game
Absolute Legend!!
This has happened to me twice on the version I play on my switch. I thought the port was buggy! Thank you for explaining this Decino I never knew this!
I missed this voice
Every time I watch this video, when you first name it "The Intercepts Overflow" I envision someone telling a scary campfire story, and I can just imagine the pause for effect right before "The Intercept Overflow". Brilliant, haha. Thank you for the DOOM analysis videos!
Hello you absolute legends!
Thanks, Decino! I was really hoping to see the "crushed enemy resurrection" bug mentioned on your channel! I had no idea there was a separate ghost bug.
I already covered those in the Arch-vile video.
THE RIDE NEVER ENDS!
I now need to make a meme with like around 40 mr bones revenants and make some overused plutonia joke along the lines of "Welcome to the Casali Brother's Wild Ride - The Pain Never Ends!"
Been playing doom for 20+ years and I've never seen this bug once, what a great explanation of something so cool and rare. Thank you!
This leads to the very mysterious question: "Who asked?" Well, to understand the question, we have to understand the answer: So this very particular question is asking about who asked, the question is divided into two parts: Who & asked "Who" is what is called an "Interrogative word" which specifies the answer to make it suitable for the question, the "Who" here is specifying a person/human/homo sapiens/guy which has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human. Second: "asked" is a verb in the second condition of the forms of the verb, which are divided into three types: Regular, Past, or Past participle. and the verb "asked" is in the "Past" condition, which talks about the time that is gone and no longer exists. The original form of this particular verb is "ask", which is to say something in order to obtain an answer or some information. So, to summon what the answer wants from the previous two points, it's that: The answer wants to understand and know about the person/human/homo sapiens/guy who wanted to say something in order to obtain an answer or some information. So, in order to answer this question, we will have to identify two points: First: What was the question that the subject of the answer to the question "Who asked?" asked? Well, to understand this question, we will NOT have to understand what is the answer. We will just have to understand the definition of "Question" The "Question" is A sentence worded or expressed so as to elicit information. Questions could be identified using the "Interrogative Words", which we talked about earlier. these "Interrogative Words" are nine, which are: Who, What, Where, Why, Which, When, Whose, Whom, and How. We are going to explain each individually: As we said earlier: "Who" is specifying a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human. "What" is specifying a non-person/non-human/non-homo sapiens/non-guy who either does not have a brain that he can understand and think properly with, like plants, or objects, or they have a brain, either that their brains cannot understand and think properly, like animals, or their brain can understand and think properly, but their species/type is rather different from the society, like extraterrestrial creatures, so the answer should be as I said in the abstract: A(n) animal, plant, extraterrestrial creature, or object. "Where" is specifying a place, city, country, continent, etc. where something happens, or some(one/person/human/homo sapiens/guy), plant, animal, extraterrestrial creature or object which exists in a place, city, country, continent, etc. "Why" is specifying a reason for doing something. "Which" is specifying a choice of either two or more choices that the receiver of the question usually chooses. "When" is specifying a time in which either something already happened, or something will happen in either near, or far future, for example: "When will anyone save me as I was captured by MatPat for trying to comment a joke about his video?" "Whose" is specifying a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, and that person/human/homo sapiens/guy owns something, or someone ( if he is a human trafficker ), and the sender of the question is trying to find who owns that something, or someone. "Whom" is an old-fashioned term, not often used today. Many native English speakers are less than clear about its accurate use. In fact, the word serves the same purpose as "Who" questions, which as we said: specifies a person/human/homo sapiens/guy who has a brain to think about the surrounding stuff which surrounds him, which distinguishes the person/human/homo sapiens/guy from animals, plants, extraterrestrial creatures, or objects, so the answer should be as I said in the abstract: A human, but tends to be used when it is the object of the verb. With modern English, there is no real need to use the term. "How" could be referring to the way something is done or refers to the status of the receiver of the question. Now, let's get back to where we were talking: Questions can be different, and many, and the possibility of guessing the question could be high or low according to the frequency of using it, but guessing a question which was asked for the first time is very difficult, so, it is not specific what was the question that the subject of the answer to the question "Who asked?" asked. Second: What is the purpose of the question "Who asked?"? Well, it could be referring to roasting someone as the humor of "No one asked.", and it could be referring to actually asking a question about who asked the question. So, here's the answer to the question "Who asked?": It could be anyone who made something unlikely for the others or someone who asked a question which could be a hint to treasure, or a last "sentence" from somebody, or something else. (s)He could be you. (s)He could be me. (s)He could be Elon Musk. (s)He could be even your mom. as long as they have made something unlikely for the others or they have asked a question which could be a hint to treasure, or a last "sentence" from somebody, or something else.