Why couldn't I beat Holy Hell?

Imagine at the end of your 5 hour plus playthrough of a brutal doom map, some inexplicable bug occurs that prevents you from being able to beat the map, well that's what happened to me.(Just to preface, I played in DSDA-Doom) Normally at the end of Holy Hell you go through a teleporter which sends you through a teleport sequence that leads you directly to the end of map, but for me those teleporters didn't work, and I have no idea why. At first I thought that monsters must have passed through one time teleports and caused them to disable and indeed they are one time only, except for the fact that the lines are also monster blocking, making this explanation impossible. What confuses me even more is that when I start the map from the beginning, the teleport lines are green on the automap (showing that they are teleporters) but when I reload my save from near the end of the map, the lines are not green, meaning that something must have used them at some point between the start and end. So that begs the question, what could've possibly broken these teleporters?

best to open it up in doombuilder and check it out, just because there is a monster blocking linedef doesnt mean it cant collide, i.e. it could have been a grab like a zero grab.

Congrats on getting that far tho, Holy Hell kicked my ass the first time i touched it and i put it down and said "i gotta git gud"  shame the save softlocked you

How were you playing Brutal Doom is DSDA Doom?

Might have been a fireball or something. What map format is it built in?

A likely explanation is that you were playing in a vanilla complevel and the teleporter lines were used up by revenant missiles.

While no missile may teleport*, some types are still able to activate special lines. In particular, missile types new in Doom2 are not prohibited from attempting to activate teleporter lines, even though that activation will always fail. In vanilla, this activation will still consume a single-use special, even if it failed (this was fixed in Boom).

In this map the cyberdemons on the towers tend to get into fights with the revenants on the mountain (the stadium bleachers?) to the east. As the cyberdemons are overwhelmed by clouds of revenant missiles, the remainder of the cloud flies through the tower, over the surrounding teleporter lines, using them up.

Holy Hell is from a time before strict adherence to compatibility level was commonplace in map testing. Many maps from back then unintentionally depend on bug fixes or other silent behavioural changes in enhanced engines, without actually using those engines' features.

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* Unless it explodes on the exact same tic it hits the line -- this happened to vdgg once

2 hours ago, Faceman2000 said:

How were you playing Brutal Doom is DSDA Doom?

I think that was a lower-case-b brutal map, not a capital-B Brutal Doom.

Ah that makes sense haha.