SAS4 nightmare pods bug

Due to the way the mission is designed, you're required to destroy the first nest, then the second two, then one more. Nightmare mode replaces a medkit in the hallway with bloaters with another nest, but the devs didn't add a check to the game to make sure you destroy both, only the medkit-replacing one (destroying the original final one only without the medkit room one doesn't open up the path) opens the door to the boss room, so you can skip the final one and let it continuing to spawn zombies. This doesn't have any purpose outside of assaults with killing spree though, but killing spree can be kept active due to it.