I've been doing some runs of map 07 any% on ITYTD difficulty, and I appear to have found a bug of some sorts. I'm quite not sure what the trigger is, I get the best luck when I kill both mancubus at the same time, but when I do that the walls that will reveal the arachnotrons will lower instantly instead of waiting for the mancubus death animation to finish.

Here is an example:

Wonder if anyone is able to figure out the real key or push this map further.

That’s known. I’m at work at the moment but I can explain how it works when I get home if someone else doesn’t by that time.

Ah I see. Well that takes the fun out of thinking you discovered something new, but sure I'd like an explanation

Honestly I thought there was more to it when I first initially commented, and I wanted to wait til I got home to do research on it to make sure it's what I was thinking, and there isn't actually more than I thought. It's pretty simple...dead simple, one could say kappa.

Basically, this glitch occurs when 2 Arachnotrons die at the same time. It's documented here - https://doom.fandom.com/wiki/MAP07:_Dead_Simple_(Doom_II)

So effectively the same bug, just with the walls that lower after the mancubus get kill. I suppose that makes sense, I always knew the end platform could be lowered twice but had no idea the same thing happens with the mancubus walls.