Can someone explain this occurrence to me>

[shanesawkool]

I was playing Doom 2 when I came across this peculiar glitch. After uploading the video, I came across a video by Karl Jobst mentioning a glitch that goes under the alias of the All-Ghosts Effect, and I believe that this may have happened here. The video that I will link provides more information in the description. I apologize in advance for not capturing the entire screen or the audio.

https://www.youtube.com/watch?v=X-HIfyvpT5o

[Doomkid]

Is what we’re seeing you and all of the monsters walking freely through walls? If so then it’s almost certainly the “all ghosts” bug:

https://doomwiki.org/wiki/Ghost_monster#All-ghosts_effect

 

Another cause I’ve seen in the past that I didn’t see mentioned in the article is playing on a map with linedefs and/or sectors that are way too large, although that doesn’t seem to be the case in this instance.

[Stupid Bunny]

I’ve run into this glitch in a couple of my maps when playing under Crispy Doom. I had never heard of it before but seeing all these enemies suddenly unimpeded by walls or ledges streaming towards me was pretty surreal and frankly terrifying. It’s a little annoying because the problem is only going to get more likely as I add more details and stuff to the core area of the map (it was almost certainly triggered by LoS checking over too many linedefs).

[Zillah]

I once had a shotgunner on E1M2 "crawl" through the windows out by the chaingun secret. He just walked up and all of a sudden he was at the ledge, than inside. Then when I shot him he disappeared into the wall. Idk why or what, but it happens.

[shanesawkool]

18 hours ago, Doomkid said:

Is what we’re seeing you and all of the monsters walking freely through walls? If so then it’s almost certainly the “all ghosts” bug:

https://doomwiki.org/wiki/Ghost_monster#All-ghosts_effect

 

 

This seems to be the closest answer that I can find to answer my question. Thank you for your assistance in my endeavor!