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Is this the last Secret of Repentance? Or just a Bug?
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- เผยแพร่เมื่อ 15 ก.ย. 2021
- Most of us probably think The Binding of Isaac Repentance doesn't have any more secrets left to discover, however there is one strange thing happening on the Mausoleum 2 floor that could change that... this video will show you what it is.
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![Unused Achievements [Cut Content] - The Binding of Isaac Repentance](http://i.ytimg.com/vi/uGiZg81msDo/mqdefault.jpg)
Quick note here: the hidden mirror can actually spawn on other floors too. It was just first discovered in the Mausoleum Mom fight and is very common there so I rolled with it ^^ It is probably nothing but interesting none the less imo
Edit: Here is what Kilburn said about the bug to me on Twitter: twitter.com/FixItVinh/status/1438617893034467332
I have heard a mirror break sound in greed mode, i think it was at sheol or depths
Maybe it's some leftover from Key Piece 3?
The second hidden mirror can be found on downpour 2 and dross 2 floors. If you destroy it and then walk into unbroken mirror you'll start suffocating, but you can leave the mirror and you won't die. This happened on me when I was trying to beat the mother. In downpour I tried to find the super secret room and accidentally destroyed it. Which unfairly stopped me from picking up first knife piece
Im saw a vidio where someone was going into an invisible mirror and ended up in an devil deal.Also you could try to use 2 speed and spin to win to get into your invisible mirror.
Came here to say this. I think I encountered it in Greed mode when looking for the secret room, but it might have been the normal mode. Not entirely sure.
I have a theory: after beating mom's heart in mausoleom 2, you actually get teleported into an alternate mirror dimension which you can't escape from, because the mirror isn't coded for you to leave, but it's still there. This would explain why the whole floor doesnt have pickups or items but you can use the D7 to revert a room back to normal (just like in the downpour 2 mirror). I would be curious to see if you can actually spawn a working mirror in mausoleom 2.
Was my thought too but then he showed there were two mirrors in the room so i don't think the theory works out
This sounds like the most likely explanation to me, honestly.
you don't start dying once you blow up the mirror though
@@thesweetnobody6442 Maybe it's coded very differently
I had the exact same thought, but you were faster...
This pretty much _has_ to be a bug.
That said... modders, you know what you have to do.
Make an entire new floor only accessible if you reach it as The Lost which now features an even harder boss than Delirium in it? I like how you think
It's most probably that they used the mirror dimension "technology" to easily switch floors/tilesets between regular mausoleum and pre-corpse mausoleum. The invisible mirrors are probably just a quick&dirty workaround to avoid having to rewrite too much code for this to work.
Yea i dont buy it,theres things in tboi that dont make the most sense,for example when fighting the boss from corpse 1 on the second phase you can actually pass trough the floor if you are small enough and you end up in a i am error room
mirror ending les goooo
But seriously, a final floor accessed through, say, a mirror that has to be unlocked with all 3 previous alt floor's unlock conditions, would be sick. Maybe the boss room would have a mirror and a bomb spawner, and you must bomb it to start the fight!
For a mod i would suggest entering the hidden mirror with 3 of the glitch items (tmt missing no error 404) would result in a gltiched floor with only glitched items and a new boss and a character
My theory is that the mirrors were the first iteration of how players were supposed to access the Home path, but it got abandoned quickly and Kil forgot to fully remove them besides making them unenterable and invisible
I like this theory!
That's actually a pretty good theory
lol this is a very good theory, but maybe it just a placeholder to avoid players to enter to the boss rush with mama mega, and enter to the devil/angel pact, soooo the developers left that out in there
I think that the “Dark” floor is just a mirror dimension. It is an easy way to transform the floor without needing to do too much fancy coding, since the mirror dimension is already in the game.
May be it is like that trains in fallout New Vegas, where instead of making a working train they just put it as a head of a character model, so they saved a bit time, not having to code a working train carriage
problem with this is if you blow up the mirror while in a mirror dimension it kills you
bug. they reused mirror room code to create the dark mausoleum effect after killing mauso heart
yeah the mirrors are also in the same spots as the boss rush and angel/devil room
Yeah its actually super obvious that this is whats happening, i can't believe how many people think it was some kind of cut content. Game devs repurpose code like this all the time
dont think so. Switching floors was in antibirth too, but without any mirrors. They could easely use same trick.
@@papabaddad Which for some reason involves the mirror? Somehow, I don't buy it. Why couldn't they use the warp code of the mirror instead of the mirror itself?
It's possible that all alt floors were intended to have mirror worlds but were cut, and this is just leftovers.
@@TheMegaxPlus Spaghetti code isn't easy to remove ingredients from
maybe the purpose of the mirror is to change floor to be the "dead" floor. After the mom's heart fight, they might just teleport you to an identical version of the floor generated at the same time, as if it was downpour/dross 2. Now, if there was a way to spawn a seperate mirror inside the normal floor, we could see if it's correct
My only idea is that the Mirror code was reused to make the Mom's Heart room, and the exit Mirror was left behind
Boss Rush too
Are you remember keeper arg? At the beginning greed machine always broke at 109, and it looked like a bug. Then we got cut out character Edit and something that looking like a bug. Interesting coincidence, isn`t it?
sorry for mistakes, I bad speak english
With the pandemic we currently have and the fact that Repentance won't have any booster packs which could potentially have a new hidden character aside from the Tainteds... Yeah, the chance is impossible, but it's nice to think about, nonetheless.
Repentance is still being updated tho, including some cut content in the files being finished, so it's still possib!e
Sorry to disappoint you, but no, the only intended big updates for the game are the tainted update, mod API update, and void update; and we might not even get the last one due to time constraint (Kilburn is leaving Nicalis around april 2022 to pursue his own projects).
@@AgentChick wait, kilburn is leaving nicalis?
They could have hidden something special for when you manage to teleport out and explore the dead floor, it's a shame they didn't if that's all just a bug.
i think something where you can choose between several items (possibly some unique ones) would be an interesting idea.
I do not know anything about programming but it is rare that an invisible mirror appears although it could be a bug since it is something else related to the path to mother
i really hope that this is some scrapped feature that may be revisited at some point
when i first figured out all of the alt path, knife piece, mother route stuff, i was so hyped about the mirror world, and while i love the escape sequence in the mines, i also was actually kinda sad that the mirror world was only available on one single floor in the entire game. it just seemed to have too much potential to be just restricted to that floor
compare it to the escape sequence for example. once you find the 3 buttons, all of the cool stuff takes place in a seperated area, where you don't even get to keep your items. and while that is really cool, at some point every escape sequence is more or less the same. not so with the mirror world.
also i was pretty sad about how they didn't keep the gimmick of the mausoleum, where the floor had an entire second half to explore, because now mausoleum is pretty much just hard and nothing else.
but this discovery kinda makes me think that this was their try to innovate that gimmick and bring it into repentance
maybe they entirely just wanted to put the mirror world gimmick in mausoleum in the first place, and then they decided that since the original knife piece puzzle in the antibirth downpour already had something to do with mirrors (and downpour generally has that gimmick with the wraith enemy) they'd just put it there altogether, and then they couldn't figure out a third puzzle in time so they left it at 2 pieces idk, could be a valid theory
i really hope that there's gonna be more to this tho
Iirc there is a knife piece 3 in the game files
@@stefperb9531 The original Antibirth mod had you collecting three knife pieces but the sequences were much simpler (the mines didn`t had the chase sequence, it was just find three switches to open the room). They remade it into fewer, but more elaborate sequences.
@@aureliodeprimus8018 thanks
what if planetariums contained mirrors you needed Soul of the Lost to pass through?
Mucho texto
game theory: people have seen devil rooms randomly spawn in the walls after bombing them with the same mirror sound
maybe the devil room "showed up" but actually didnt?
like, the game said it should show up, but instead it got replaced by a buggy mirror thats breakable.
OR
it could be a cut feature from the old "mortis" floor
in the games code, theres code for a alternative version of corpse called "mortis"
maybe the mirror was the way to get to the secret alt?? but they cut it halfway through development and left some remnants
Have you tried throwing a full knife at it? I'm wondering if the game is trying to hide the door to the heart fight
I think it only spawns after the heart is killed
@@bruxtle That could be exactly why, though, because you can't go back through to the heart fight
Mom's knife works
@@bruxtle mom's knife can destroy the door
@@Apple80089 they are talking about the knife pieces and the hidden mirror
I actually heard mirror breaking sound during game breaking in greedier mode, when a pick-up rerolls into trollbomb, which is... much more strange
If it's a "There Has To Be A Reason" thing, my guess would be these hidden mirrors are how they get the new empty mirror floor to spawn in after the Heart fight, just instead of the regular mirror world, when you leave the room it transitions you through a door into the dark mausoleum floor with it's screen effects, and the mirrors are only there due to programming quirk which needs them to be there to stop the floors being reversed, the reason why they're not there all the time could be because something is making the mirrors spawn in the room instead of just outside
edmund: haha yeah… “secret”. definitely an intentional feature
Lets gooo ur talking in your videos now, that was the one thing that was stopping me from watching u as much as every other Isaac youtuber, keep it up brother
i think it would be neat if they implemented this as a way to access the cut alt floor for corpse
are there any leads on what that floor was gonna be?
it was called 'mortis' and i think that's all that's known
(from the wiki: "An unused floor which would have been an alternative version of Corpse exists as two empty room files with no associated assets. In the music xml there is also a listing labeled as "not done" after Gehenna which uses The Womb's theme as a placeholder. Edmund McMillen has confirmed on twitter that there are currently no plans to add Mortis to the game.")
@@arctictundrarightnow ughhh! They should add Mortis! It bothers me so much that Corpse is the only floor without an alt version.. feels rushed and unfinished
@@pinkunokinyobi home also doesn't have one
@@pykor9386 Home is just a boss fight floor, I'm talking 2-floor levels with alt versions here
There a few things that can be explained from a technical standpoint.
What you experience when you walk into a broken mirror is the same thing that happens when you change the collision type of a wall from 4 to 5 through the console / mod: it disables collision with the player and only the player. (Collision type 4 is WALL, it collides with every entity, collision type 5 is WALL_EXCEPT_PLAYER, this is one way you can create doors through the modding API).
What is interesting now is how the mirror works in Downpour / Dross II. It is basically a door, and each door in the game has a target room index. The specificity of the mirror is that its target room index is negative. Negative room indices are used for rooms that are out of the map, like the Devil / Angel Room, the Angel Shop of The Stairway, the Mausoleum Mom's Heart fight, and basically every room that is not on the grid map. The mirror is a special case, it's target room index is handled internally by the game as a special index that sends the player to the mirrored version of Dross / Downpour II (a similar thing happens with the door that exits the minecart area in Mines / Ashpit II, it has a negative room index as target, and the game instead teleports you to the special area to get the second knife piece). I guess they added a quick fix like "'Check if the floor is Dross / Downpour II before sending the player to the mirrored version", just in case a player managed to spawn the mirror on another floor.
Regarding the fact that the Mausoleum remains dark even if you restart it, this is probably an oversight from the devs. Once you defeat Mom's Heart on Mauso II, the game sets a flag that indicates the heart has been beaten, which causes the game to darken Mausoleum II and all trapdoors created on the floor will now lead to Corpse I instead of Womb II. This flag can be switched off through the modding API (GameStateFlag.STATE_MAUSOLEUM_HEART_KILLED). I think the map reveal and clear of all rooms is simply triggered once you kill the heart and that's it. A similar behaviour lead to a softlock after the release of Repentance, where using the R Key during the Ascent would not reset the game flag indicating the Ascent was in progress, so the player would be sent back to a bugged version of the Ascent version of Basement I.
Another interesting thing to note is that breaking an invisible mirror in Downpour / Dross II and _then_ going into the mirror world will actually kill the player because breaking the invisible mirror causes the game to set the flag indicating the mirror has been broken, which is how the game knows if it has to kill the player in the mirror world. So... I think this indicates that the invisible mirrors are a bug...
lol this breaked my gamer brain, but you're a really underrated person
My theory? Defeating Mausoleum Heart activates a "Mirror World" like effect but dispite being kinda coded like one, was never meant to have an actual mirror.
The mirror was made unescapable and invisible, but simply exists here as a placeholder to enter "Dead Masoleum" that is slightly janky.
I think that once youre defeated the heart in mausoleum 2 the game thinks youre in mirror world🤔.
Perhaps it was from a cut item that allowed you to spawn a mirror world on every floor since an invis mirror can spawn on any floor
As a modder, I can say it's very likely that the invisible mirror door is from a former implementation of the rotten maus II. I believe that when first making this interaction, Dimension 1 was used to swap to the rotten floor, and the mirror door would likely be on the same spot as the heart door, or something like that.
This is however no longer the case, rotten Maus II actually takes place in Dimension 0, despite the similarities, this is also further confirmed by the fact that blowing up the invisible mirror doesn't just kill you after a few seconds like blowing up the mirror in the mirror dimension does.
Internally, I'm pretty sure the game now just changes a game state flag whenever you beat the heart, to swap the backdrops and clear/reveal every room in the floor, and the mirror door is just a leftover from the first iterations of this interaction, easily forgotten due to the fact that, well, it was an invisible door, lol.
I really wish that the mirror mechanic wasn't just for the 1 floor. How cool would it be if there was an item that allowed mirrors and white fires to spawn on every floor?
or like a trinket similar to perfection and Planetarium mechanics you need to x to get that trinket
i honestly think what happens here is: when you leave mom's heart battle, you get sent to some "reverse" floor just like the one in downpour, but ed was lazy to creat a new thing from 0 so he took the stuff from the mirror in downpour
i can be completly wrong, but this is just a theory
Ed isnt developing the game himself though
Ed isn't a programmer and it isn't "lazy" to reuse features, it's smart, saves time. They just forgot to make the sound of the mirror not play here.
@@Xiaolin2 What i meant with lazy was exactly that
people always think that when someone is lazy, its a bad thing, but It really isnt
our brain itself is a really lazy machine, which is always trying to look for ways to save energy for when you actually need It
When you kill moms heart it could be transporting you to a mirror world to keep the layout the same but have an alternate way down wasn't really ment to be explored so they must've just cut the enemies that normally spawed in the normal mirror world if you could spawn a few of those reflection enemies then kill the heart and reset that room with those enemies mybr they will show up like in downpour probably not but worth a try
Edmund need to just role the repentance+ and add a secret character that can be unlocked with this "bug" and generally more features
Edith
Tbh when i saw this i thought maybe it was a leftover of the purple mauso, considering the 2 floors in 1 mechanic was in downpour now when it originially was in mauso in antibirth
This is incredibly interesting, if it is just a bug I hope they reference it in the next patch.
Your channel is great and your dedication to it too!
Dead mausoleum is creepy as hell. I remember I wanted to grab something after mom’s heart fight, so I teleported out, and it’s just that dark place with eerie music. Sprinted back to boss room like madman
my guess is part of the code was copied from the mirror area in downpour/dross and used to make the effects that happen after killing mausoleum heart. The mirror was probably added because the code depended on it to work and made invisible and blocked so you couldn't break the game by going back to normal mausoleum II
I've already done all this research with one of my friend and discovered the same things but i was thinking i was crazy, very cool video
Creepypasta authors:
Write that down, write that down!!!!
My best guess is the dark floor was made from borrowed code of downpour. The alt floor version relies on a mirror spawn so maybe it gets instantly despawned and sometimes bugs out
my thoughts say that the mirror is what allow the new color scheme and everything else for the floor to happen. the lack of enemies is youre not meant to leave the boss room and so, never explore any of the rooms. the mirror being a piece of code that tells the game to warp the player to different floor and is triggered when you leave the heart room
I remember thinking this when I bombed certain walls and a random mirror shattering sound would play. It’s not just on mausoleum, and can appear on caves and mines from what I can remember.
An interesting thing that happenrd to me is that after defeating mom corpse (the witness) in repentance i got out of thr game and came back and i noticed it was a door, i didnt see it until i was doing the animation of getting in the chest
i hear the mirror shatter sound all the time in greedier mode when explosions go off lol
The fact that all of the rooms are empty gives it away - the 'corpse' floor is simply a fully cleared mirror version of the Womb floor. Remember that when you go into a mirror, all shops and secret rooms are also completely empty.
The breaking mirror is likely just some leftover traces of how that mirror floor was generated and I'll bet that if you bomb every wall on a floor, you'll eventually find one that contains the 'mirror' every time
WOAH. thats really cool. hope you find more!
Wow, i didn't expect something like this
That must to be an error
Theres nothing special, just yet another repentance bug here. But tbh would be cool if when you use the fool after mauso heart there will be something special on empty floor
I've encountered the same 'glass-breaking' sound outside of Mom's boss room, outside of the alt-path even - in Necropolis II and some other floors too, I think. It just happens sometimes when I look for the secret room.
once playing as tainted lost found a "mirror" like this on mines 2, it got me to the devil room
i found that invisible mirror in greed mode once
it was at the place of the devil/angel room, so maybe it as something to do with that door despawning wrongly ?
That area is a coded part of the game, which I think would be like the mausoleum floor in Antibirth, but since they didn't implement it.
it feels so weird hearing the calm outside of a completed boss room
An interesting note is that unlike the mirror world, the map isn't flipped, but like the mirror world a visual effect is created on top of the screen. It literally shares almost every property except the map flip.
idk if the bug was fixed, but i remember finding a bug where the death certificate area killed you if you broke the downpour 2 mirror on the floor you used it on. i wonder if death certificate would kill you if you broke one of the invisible mirrors
omg thanjs for the vieo SLAY its so cool and misteryous its probebly some-thing importent
I actually remember getting this on depths 2 while looking for the super secret room. Mirror broke, but it was invisible and outside the boss room
They (mirror and flesh door) probably just share the same code, only with different visuals and destinations, so when you leave flesh door it thinks there should be a door back, maybe try opening it with knife again, instead of being lost
The same hapends at greedmode, every time you get out of every deal room
The slowed music reverbed music is frightening, and I love it.
I have a theory: since mirror side of dowpour/dross shares same mechanics as „dead mausoleum" (empty shops/item rooms) . That might mean that mausoleum heart is just another room like boss rush room but when you leave you change to „mirror mausoleum " but Ed made the mirror invisible and removed the white corners of screen, flash right before entering/leaving mirror world and lost form.
Maybe try items where you can shine light or take away the darkness effects, or maybe try to spawn mirrors on all 4 walls?
I've seen the mirror sometimes but not always working. It's taken people to the Devil Room before.
You can stumbled into them as lost and they sometimes have devil deals in them
Your accent is just the single best thing in the universe
I remember watching bd1p's random streak video where he was looking for a secret room in Ashpit (I think) and he was shocked when he randomly heard the mirror-shattering noise
I’m scared of dead floor after heart fight. Everything so… empty . You just wandering around in dead rotten rooms with muffled music in background that reminds me funeral march.
One more mystery:
Ashpit room d.694 has a visible hole in the bottom right corner wall. If you have flight, you can move through the hole and into the out-of-bounds area in the corner. Not sure if there's any more to it, or if it's just a wacky easter egg
Probably was gonna be something more to it but was cut for reasons I’m not sure of. Probably was cut later on developed to make way for beast. This was probably left in the game or it’s become a bug or maybe a combination of both
yep, knew about the item disappearing thing; i got an angel room but went fighting the heart. Turned back and there were no items inside lol
My theory what that will be path to unlock new alt version of corpse - mortis, but that in new update can be anything instead mirror, so we will see
I heard that sound when I put a bomb where the devil's room appears normally in greed mode, so maybe its a bug
The Planetarium with a dark background is pretty spooky
Mom gets up after her heart dies and as a last ditch effort resets the floor
Maybe the mirror could be like a new floor? Maybe a mix between the catacombs and the corspe desolation feeling and death?
Maybe this could be a New Boss Room or path for a future patch
i wonder if there is some secret with the mausoleum boss visage because the empty mask is still there after the kill and you can push it around in the room
My first thought is maybe instead of teleporting out of the room you would instead go back to fight dogma through the mirror realm to home, like Dad's note. As it defeats the purpose of having to teleport out of the room/the fool card.
The entire floor is a replica of the floor and is empty bc it wasnt implemented. Otherwise itd act the same as going to mausoleum 2 before taking dad's note.
It just seems to be how they made the change to the mausoleum, it ports you to a different world using the same mechanics of the mirror one, with the fake mirror unusable door left hidden but apparently not enough for people to not find it eventually
maybe it’s some sort of short cut that uses a similar coding technique to the mirror world in the second alt floor used in the mausoleum and the mirror is a kind of left over
I guess that the mirror spawns in random location of the map, to make alt floors code as mirror rooms. The mirrors dont have a usage but they may be needed to use the same script
Maybe it's the Glowing Hourglass thing, that if you use it in the starting room (as eden, of course), you instantly get teleported to Home.
could this be a hint of some special final thing that will be added in the last patch of repentance
My suspicion immediately was that it was something to do with generating a new down floor: they had to change the direction that going down a floor would take you, even thru an I am Error to Corpse instead of Womb, and maybe they used a similar process to mirror worlding to do so in the background. Few holes in the theory: that this happens on other floors, that trapdoors in mirror land are just like regular trapdoors
I actually had this happen in ashit instead of after the mom fight when i tried looking for a super secret room.
would be pretty cool if they made a callback to the "second part" of the mausoleum floors that existed in antibirth
even cooler would be if that invisible mirror lead to said "second part" but all abandoned
maybe a similar code is used to create the dark mausoleum as the code used to create the mirror world and the mirror spawning is just a leftover that they didn’t manage to completely remove in time
What's the "boss defeated" theme that plays after you beat Mom's Heart? I can hear it play more prominently when he teleports out of the post-Mom's Heart boss room into the empty "blank floor" but I can't really find it anywhere when trying to look it up
I know occasionally on T. Cain runs, sometimes a troll bomb explodes and I hear the mirror shatter, even in Greed Mode where there is no mirror at all.
Seems like the "Dark floor" is the mausoleum's version of a mirror world. The mirror might be there to make the transition easier or maybe left over from testing the transition. I dunno.
1: the way it works is the same as ascend - the floor just changes after sertain situation. also, as i remember, with forget me now on this floor some rooms doesn't work the same as before (in shop nothing for sale, in treasure there is no item)
2 - was that reported after so much time? Like, i got Isaac during Sommer(in june if being exect) and i already found out about everything but mirror
Read this somewhere in the comments, but it could be trying to disguise doors that disappear after leaving the room, such as angel rooms, devil rooms, and the flesh door. That would explain why it's in the mausoleum mom room and only sometimes in other rooms. Don't know why they'd use a mirror, but that's just my assumption.
Although an alt alt path would be really cool, too.
I think this crops pass flor work same as mirror reflection flor. When you kill heart in flesh room door replace with retextered mirror with needs another one for work. I don't know how they may do the same thing without recoding whole game and using that ready to use mirror trick
i remember this happening to a friend of mine, i think it lead him into a devil deal somehow. definitely a weird bug
imagine this: you use the fool and you go around the floor looking for the rooms you missed or maybe to get some hearts back (its curse of the lost), but hey, you found an... open planetarium... you dont remember ever going in there and opening it, but because its open you go in, and in there you find nothing, just emptiness and nothing not even the stars in the background are present, you get kinda creeped out so you decide to look for your pickups which you swear should have been in these rooms you've already visited, you go in the shop hoping you will be able to buy that soul heart (you have those 18 cents after all) but nothing is in the shop, besides the donation machine, so naturally you decide to donate to it, after a while of going around all over the place you decide to come back in the boss room, but where is it? after a while you find it and you get a creepy feeling theres still something else other than you, after entering the boss door you go down the hole with all of your worries disappearing as you see corpse I.
in my quest to finding what wasbehind the door in depth 2, i tried to bomb every wall. Once i heard the shattering noise of broken glass. I realise now that it was one of these hidden mirror. But i lost alot of time thinking it had something to do with the door.
I think that's to avoid the player from being unable to access Corpse after using Forget Me Now, since you don't get the knife back after restarting the floor.
Probably was a way to unlock Tainted characters before they added the Dogma path.
What if u have the knife familiar after the heart fight, the only way I can think todo this would be to get r key to have double the knife familiars but maybe it would be able to interact with the mirror?
My theory (based off of a video I watched of someone playing Antibirth) is that this is a leftover of how'd you would get a third knife piece in that mod. This was via teleporting to extra rooms in Mausoleum similar to Repentance's mirror world, meaning that they might've had this in Repentance at some point but then scrapped it in favor of the new way to get to Mother.
This kinda reminds me of the one time on a cain run i defeated mother and used the r key to do the beast path, but after defeating mom i went to mauso and it was a "dark" floor which meant that all items were gone, including dads note which softlocked me...
after entering devil room and leaving it i exploded place where devil room was
and i heard mirror too
Maybe it's used to change the colors of rooms, basically forcing you trough a mirror when leaving the moms heart room.
Like many others have said it already, you definitely just get teleported to a mirror dimension after beating the heart