Doom Trivia Thread

[MajorFoley]

blue armour is best waited till you are around 50% before you get green armour as you still get more protection (i believe 70% or so) while green offers around 50% or less

[Phobus]

Blue armour is 50% damage reduction, green armour is 33%

This means that, really, you want to hang on the blue as long as possible and keep it boosted with armour helmets as your health will always take more damage when you're wearing green.

In practice though you'd get more long term protection from green once you drop below about 40 or so blue armour. It really depends on how much health you have to lose and how long you want the armour to last. If you're taking on hordes of hitscanners, green sometimes makes more sense as it will last a long time against the low damage their attacks do.

[finnw]

The Revenant is the only monster in DOOM II with three weapons (if you count homing and non-homing missiles as separate weapons.)

[Maes]

The revenant's missile has the highest standard damage of any projectyle -up to 80 HP- making it almost as dangerous as a direct cyberdemon rocket hit, and a one-hit-point-wonder death for an unarmored player with HP <=80. And the fuckers are used in HORDES ;-)

Due to this high damage and its use of homing missiles that almost never miss, the Revenant is able to defeat apparently tougher monster in an infighting, if the exchange is mostly projectile based.

E.g. a Knight has less projectile damage and more chances of missing, so it's not unheard of to see Revenants surviving one-on-ones with Knights and Cacos, while two of them can easily give a Baron grief. Also, its melee attack has a timing that may disrupt even melee combat, still giving it an edge.

Also: the revenant's map object height is just the same as zombies and the player, so it can "squeeze" through apparently too low hallways without problems, even if it LOOKS tall ;-)

[The_MártonJános]

Maes said:

Plutonia MAP12 has a single rogue Thing of type 0 (thing 225 at X: 1600 Y: -3104 ) which is invalid and yet is not caught by vanilla checks, due to priorities (gory details here).

Speaking of Plutonia MAP12, earlier versions of Doom had a teleport screwup in the level, seen in this video between 2:52 and 3:07. Translating the speaker's speech between that interval: "I had a close-to-death experience at one of the teleporters. Yep, what the heck was it, let's see it again... well, a slight sight failure... I swear I didn't use cheat codes!"

[Daiyu_Xiaoxiang]

In TNT map22, the player can access to the exit straight forward without getting any keys.

[Maes]

Cell said:

Speaking of Plutonia MAP12, earlier versions of Doom...

Were there different official versions of MAP12 released? Or is he using a source port?

In any case, I've seen similar "screwups" with deliberate easy-to-trigger teleporter puzzles.

[Six]

Daiyu_Xiaoxiang said:

In TNT map22, the player can access to the exit straight forward without getting any keys.

You can do the same thing in map31 too, although it's not as straight forward. Never needed the missing yellow key to begin with.

[Gez]

There exist a very rare version of the "Id Anthology" pack which features bugfixed IWADs for TNT: Evilution and Plutonia.

Speaking of which: The TNT and Plutonia IWADs (either version) contain _DEUTEX_ lump, showing they were edited with DEUTEX.

And still speaking of which, though it's more a "third party Doom tool trivia" than a "Doom trivia" thing: DEUTEX checks for the presence of the string "IZNOGOOD" in its _DEUTEX_ lumps. Olivier Montanuy must have been a fan of this comic.

[Grazza]

Processingcontrol said:

If you walk all the way across a level's void space with IDCLIP, you'll end up at the other side.

You don't have to be using IDCLIP.

[printz]

Grazza said:

You don't have to be using IDCLIP.

Sometimes warping through walls happens without any effort or intention from my part. Doom can be quite unstable some times.

[Janizdreg]

You can make revenant and arch-vile fights very easy in vanilla if you just do a fast quicksave/load combo while an arch-vile is flaming you or a revenant missile is chasing you. Using the trick makes revenant missiles lose their tracking ability and makes the in-progress arch-vile attacks completely harmless, both due to the same bug. And yes, it's also a lame cheat and only a wuss would use it. :-P

[elic]

Bugs are like that make me wonder why people save.

[Daiyu_Xiaoxiang]

Six said:

You can do the same thing in map31 too, although it's not as straight forward. Never needed the missing yellow key to begin with.

Actually this is deal to a yellow key bug in this map.

And PL2 map27 got the poorest teleporting system ever other from Cchest2 map13.

[Grazza]

printz said:

Sometimes warping through walls happens without any effort or intention from my part. Doom can be quite unstable some times.

The most common reason for that (apart from an horrendous mapping error) is an intercepts overflow. But it's very rare for this to be useful, as there are very few maps where you can then exit - you need to reach an "damage/exit if health <10" sector.

[printz]

Grazza said:

The most common reason for that (apart from an horrendous mapping error) is an intercepts overflow. But it's very rare for this to be useful, as there are very few maps where you can then exit - you need to reach an "damage/exit if health <10" sector.

No, no such intercept overflow in my 2 cases where it happened. I was simply moving randomly through a monster-empty map, at a none too large speed, and it happened to me to glide through a wall or grate without intending to do so, without forcing myself. I think that angled grates or walls are susceptible to this, right?

[Grazza]

Sure, but I thought you were talking about ways to reach the void.

[Maes]

Janizdreg said:

Using the trick makes revenant missiles lose their tracking ability and makes the in-progress arch-vile attacks completely harmless, both due to the same bug. And yes, it's also a lame cheat and only a wuss would use it. :-P

Actually, it's perfectly possible to reconstruct infighting even from saved vanilla savegames. Fraggle (?) had done some research to show that it was theoretically possible (by doing some guesswork with the saved pointers) and I even managed to do so in Mocha Doom, being able to load 10-yo savegames and restoring their infighting.

[finnw]

Maes said:

Actually, it's perfectly possible to reconstruct infighting even from saved vanilla savegames. Fraggle (?) had done some research to show that it was theoretically possible (by doing some guesswork with the saved pointers) and I even managed to do so in Mocha Doom, being able to load 10-yo savegames and restoring their infighting.

How does that work? Is it documented somewhere in /idgames?

[MajorFoley]

in one of the old versions of doom 2. there was a bug where if you killed an enemy while the arch vile was still in the process of reviving it. it would become a ghost enemy and would be invulnerable and still be able to do damage to you (happened to me when i tried killing a demon while he was reviving it)

[Grazza]

There weren't big changes in the internals of the engine between Doom2 1.666 and Doom2 1.9. I suspect that whatever you observed was just the standard AV bug, and killing the monster while it was being revived was purely incidental - the only thing that mattered was that, at some point before being revived, the monster had been flattened by a crusher or by leaving its corpse under a door that closed.

[elic]

MajorFoley said:

it would become a ghost enemy and would be invulnerable and still be able to do damage to you (happened to me when i tried killing a demon while he was reviving it)

Ghost monster can be killed by blast damage; if you shoot a rocket at a wall they will be hurt if nearby.

[MajorFoley]

Processingcontrol said:

Ghost monster can be killed by blast damage; if you shoot a rocket at a wall they will be hurt if nearby.

ah never knew that thanks lol

[Maes]

finnw said:

How does that [infighting reconstruction for vanilla] work? Is it documented somewhere in /idgames?

Well, anyone can take a peek into the savegame/VanillaDSG.java file of Mocha Doom, no big secrets there.

A -very- simplified explanation is this: in vanilla savegames, thinkers (including the player) are always stored in a predictable relative order and have pointers to the next or previous thinker. These, per-se, are useless, because they refer to actual memory locations that have become invalid ever since you saved the game. However, they are UNIQUE, and that helps thing out:

E.g. the first thinker found in a savegame may have a "next" pointer of "A" and the next archived thinker will have a "prev" pointer of "B" etc. Since those WERE actually sequential even in memory, due to the way savegames worked in vanilla, I can construct a table telling me "the first thinker has a pointer/hashcode with value "B", the second thinker has a pointer with value "A" etc. and I can identify which thinker used to be the player. Then, whenever I encounter a particular pointer value in other fields (e.g. target, tracer etc.), I can "rewire" thinkers to other thinkers (there is a reconstructPointers() and a rewirePointers() method). This restores infighting, chasing and tracer targets using information available in the savegame itself. It works so well, that I "mimic" vanilla saving by saving object java hashcodes instead of progressive indexes.

Again, the method/possibility was first described by fraggle (correct me if I'm wrong), but I'm not aware if any other port applies it to vanilla savegames.

[j4rio]

Maes said:

The revenant's missile has the highest standard damage of any projectyle -up to 80 HP-

HK/Baron scratch can deal 80 damage as well

[Maes]

j4rio said:

HK/Baron scratch can deal 80 damage as well

Yeah, but that ain't a projectile, is it? It's this asymmetry between ranged/melee attack that gives the Revenant its power vs even apparently tougher monsters.

[j4rio]

Nope, but it's also a common way to lose 80 HP. Besides revs are quite fragile, so that makes up for it.

[MajorFoley]

j4rio said:

Nope, but it's also a common way to lose 80 HP. Besides revs are quite fragile, so that makes up for it.

thank god for that eh? i just get a rocket launcher or SSG and nail em

[D_GARG]

former sargeants shoots 3 pellets wile you shoot 7 with normal shotgun, and still you're getting your ass kicked by 2x3 pellets, in deathmatch you can survive up to 3x7 pellets from a players shotgun.

DECORATE: Double Chaingunner shoots 2 pellets/bullet sequence, I belive.

[Vermil]

D_GARG said:

in deathmatch you can survive up to 3x7 pellets from a players shotgun.

The maximum damage of a single player Shotgun shot is 105 (7x15), therefore it can potentially kill a 100 health player with no armour, in one shot.

Of course wheter Doom's random number generator could ever allow all 7 pellets to do their max damage and then the odd's of it happening...