Weird Doom Bug

I was playing Doom 2 in glboom-plus, and I got to map03. When I went to the outside area, I starting shooting at an imp. I was about to finish it off, but then I realized that it was just standing there. I walked around it, and nothing happened. So I hit iddqd and killed everything around. Nothing happened, so I ran into it, every time I touched the imp it immediately turned to face me and started attacking. When I walked away it just stood there again.

I wasn't recording a demo, but I took some terrible screen shots.






Maybe it got stuck on the ledge somehow?

Yup - monsters get stuck on ledges that they can't cross. It happens a lot with lifts.

It's a variant of the "monster hanging off lifts" bug, as described here.

What compatibility level did you use?

That doesn't happen in vanilla.

It may happen in Boom or other engines imitating Boom, where things can get (partially or fully) pushed over ledges while alive.

myk said:

What compatibility level did you use?

That doesn't happen in vanilla.

It may happen in Boom or other engines imitating Boom, where things can get (partially or fully) pushed over ledges while alive.

Well, it wasn't pushed. It barely caught the edge of a shotgun blast, and then it walked all the way over to the ledge and got stuck there.

I used the default glboom-plus compatibility level, whatever that is.

Edit: Oh, and the imp was also able to use projectiles to attack when I got close enough to touch it, according to the wiki page that doesn't happen in vanilla.

myk said:

That doesn't happen in vanilla.

What does happen? Are ledges just treated like monster block lines? Except they can fall over them if they're dead though right?

bgraybr said:

Edit: Oh, and the imp was also able to use projectiles to attack when I got close enough to touch it, according to the wiki page that doesn't happen in vanilla.

Actually the Imp uses a combined action for both it's melee and ranged attack.

Regardless of wheter the imp starts an attack when you are at a distance or in melee range, your distance when the action is called at the end of the attack, will determine wheter it launches a fireball or claws you.

40oz said:
What does happen? Are ledges just treated like monster block lines? Except they can fall over them if they're dead though right?

Exactly. The imp could get stuck that way, while alive, only if standing at the edge of a lift.