Unusual battles

[The Ultimate DooMer]

I just witnessed this fight while playing Memento Mori map 21 - a hell knight fighting another one. I was lucky enough to get a snapshot of it, and the funny thing is that towards the end of the same map, there's a room with 3 pics of 2 barons fighting each other. Weird!

I was wondering if anyone else (apart from the MM team of course) has seen any similar battles, as I bet it's quite rare. (it's the first time I've seen anything like that)

(1000th post!)

[Ichor]

I've seen enemies fight with themselves before. In Hexen, a Chaos Serpent shot a fireball at me, but it hit a tree instead. It burned down, and it was close enough to cause a tiny amount of damage. It was enough to get the enemy to start attacking the one who destroyed the tree, which was...himself. He just stood there chomping thin air, but because he was the target, he took damage from every melee attack. Eventually he "ate himself to death" (guess where this quote is from, heheh).

[Little Faith]

This is probably what has happened:

One of the hell knights hit a barrel with it's goo causing it to blow up in the face of the other. The other got angry and attacked.

While they can't damage eachother with their green goo, they can rend eachother apart with their goo.


This has been common wisdom in quite some time, most of the time E1M8 of the original doom is the example level cited.

[fraggle]

In the early versions there was a bug where if a monster hurt itself (eg. blowing up a barrel), it would take itself as a target and tear itself apart.

[magikal]

Yes I've seen it many times. Have a look here. This is a great classic site, if you haven't seen it, enjoy.:)

[The Ultimate DooMer]

It must be that, as there are barrels up there, and I went back and did it again. (this time I got both of them to fight each other - like this)

Incidentally, the left hell knight is about to land the killing blow...

[Ichor]

I wonder... Can this method be used to get a Cyberdemon to fight another Cyberdemon? I doubt they will be able to kill each other, but it would still be fun to watch.

[magikal]

Ichor said:

I wonder... Can this method be used to get a Cyberdemon to fight another Cyberdemon? I doubt they will be able to kill each other, but it would still be fun to watch.

No, but it would be great to watch, heh.

[magikal]

fraggle said:

In the early versions there was a bug where if a monster hurt itself (eg. blowing up a barrel), it would take itself as a target and tear itself apart.

Yep, this is there too.

[Little Faith]

Ichor said:

I wonder... Can this method be used to get a Cyberdemon to fight another Cyberdemon? I doubt they will be able to kill each other, but it would still be fun to watch.

They would never be able to kill each other. A cyberdemon is immune to cyberdemon rockets. It has no close combat attack. Consequently a cyberdemon has no means to kill other cyberdemons.


I once heard that pink demons could be made to attack each other, but I can't remember how.

[BlueBeast]

for what it's worth, i accidentally caused a hell knight and a baron to fight. They were coming after me, so i waited to shoot for when they were both passing a barrel (one on each side).
I was kinda amazed cuz i knew it was a glitch. Also for what it's worth, the baron won and indeed killled the hell knight. Most of it's a blurr what the attacks were because i was just watching with amazement.


Thats my 2 cents worth

[Megalyth]

I've seen two demons fight. I think it was e2m1, in the marble room with the two skull switches. I dodged to the side as another demon stepped in and caught the bite somehow.

[Job]

I was playing Doom 1 and I exploded a barrel next to a baron of hell so that he got hazed by the explosion. For some odd reason, he faced where the barrel was and was scratching at thin air. It seemed to hurt him as he did this...maybe he was fighting a phantom baron or just some weird Doom ju-ju?
/edit

Whoops, sorry about that one -- but the baron didn't hit the barrel. I did.

[Little Faith]

This has been mentioned before in this thread.

He probably hit the barrel himself. As he figured that he was under attack from himself he began attacking himself.

[dsm]

Little Faith said:

I once heard that pink demons could be made to attack each other, but I can't remember how.

I experienced that a looong time ago. Damn it was funny to watch them munch away at eachother :-]

Oh yeah and I've experienced it with both Hell Knights, Barons and imps.

I once dreamed that I got two Archviles burning away at eachother, dunno if that's actually feasible.

[The Ultimate DooMer]

I've seen archviles blow themselves up with their spell (by taking away most of their hit points and then standing right in front of them when they attack) but I don't think they can blow up barrels, so probably not.

[myk]

They should be able to blow up barrels, since their blast has an area effect similar to rockets'. Nonetheless that would not transfer the damage as belonging to the attacker*, I think, so a fight wouldn't happen.

It's not uncommon to see Arch-Viles die when they attack Cyberdemons from close up, due to their own attack.

Also, I believe it might be possible to make a Cyberdemon attack another, distracting the first one. The second Cyberdemon would ignore the attacking one, though.

* I've been told Arch-Vile attacks are special in that they don't "belong" to the Arch-Vile, thus they never get attacked for hurting anyone.

[Cyb]

Cyberdemons aren't hurt by any sort of splash damage, including barrels, so it's impossible to get them to fight short of turning on monster infighting (as far as I know anyway, I may be wrong about the barrel thing).

You are right about the arch vile thing though, for some reason their attack doesn't "belong to them" (probably because it's not aprojectile) so when amother thing gets attacked by it they set the arch vile attack, rather than the archie, as their target. Of course by that time it's gone and there's nothing to attack.

The demon infighting is particularly cool though because I have no clue why it happens, but too many people have reported it for too long for it to be any sort of hoax. If you sift through the source you'll find that when a demon attacks something it's applied directly to the target (as long as the target is within range at that given moment), not via a tracer or anything like that, meaning it's impossible for a demon to miss his attack (if the target goes out of range the attack is simply not applied), so how it happens is a mystery to me.

I have seen demos of hell knights bashing each other though, which happened on barrels of fun. If I can find where the demo is I'll point everyone to it.

[Ichor]

The only possible way for Demons to miss their targets like that is if it was a shadow, i.e. Spectres or players with invisibility.

A very easy way to get Demons (or any monsters) to fight each other is to simply die. They will then turn on each other. They probably won't start attacking each other if you die by something like lava or a bad rocket shot.

[Amaster]

I've sen all of the above happen. But im pretty sure that Ive seen enemies attack the Archie (it was a cyberdemon) I could be wrong though.
The funniest is watching a group of Lost Souls taking each other on.

[myk]

We can assume the Arch-Vile works like that on purpose so that other monsters wont get pissed with it. I doubt it's a side effect of something else.

As for the Demons, what about when they attack a partially invisible Player? I have seen them bite at thin air... could one possibly bite another Demon beside it in a melee? Or do you (Cyb) mean that those attacks at thin air could never trigger the actual damaging frame?

[magikal]

Cyb said:

I have seen demos of hell knights bashing each other though, which happened on barrels of fun. If I can find where the demo is I'll point everyone to it.

See the links in my previous posts for screenshots and demos of 2 Barons fighting and many other Doom bugs and weirdness.

[myk]

Ichor said:

The only possible way for Demons to miss their targets like that is if it was a shadow, i.e. Spectres or players with invisibility.

A very easy way to get Demons (or any monsters) to fight each other is to simply die. They will then turn on each other. They probably won't start attacking each other if you die by something like lava or a bad rocket shot.

I don't think Spectres affect other monsters like the Player does. I mean, they aim properly at Spectres. Also, monsters will fight each other after the Player dies only if they would have done so normally without being attracted to you (as a target) since they can remember previous targets to a degree, I believe. At least it seems so from what I've seen. I recently saw a Revenant finish an Imp and then go forth to attack another Imp that had hurt it earlier. Someone who's checked the source on this would know better, though. what I mean is that such an occasion (the Player's death) adds little or nothing to this, except that the Player isn't there to be a possible target.

[DooMBoy]

Heh I remember once at the end of E1M3, I blew a barrel up, and all the imps started blasting each other with fireballs and scratching each other. It was pretty cool.

[Fredrik]

DooMBoy said:

Heh I remember once at the end of E1M3, I blew a barrel up, and all the imps started blasting each other with fireballs and scratching each other. It was pretty cool.

If you blow up the barrel, the imps won't attack each other, heh.

[Cyb]

Demon attacks don't work like errant projectiles, they can't "miss" unless the player (or monster) backsteps them while they're in the midst of attacking. I believe the demons have four attack frames and the actual attack occurs in the third or fourth frame, so you need to move out of range before that frame comes up. If you do, they continue their attack frames but no damage is applied to anothing. If you don't they hurt you. Damage is applied directly to a target. I'll sift through the source code in a bit to check it out further and also to possibly correct myself hehe.

[Cyb]

Okay, here we go, whee, this is from p_enemy.c in the original source if anyone is interested:

void A_SargAttack (mobj_t* actor)
{
    int		damage;

    if (!actor->target)
	return;
		
    A_FaceTarget (actor);
    if (P_CheckMeleeRange (actor))
    {
	damage = ((P_Random()%10)+1)*4;
	P_DamageMobj (actor->target, actor, actor, damage);
    }
}

That is the demon attack function (recall the demon sprites are named SARG* just so you don't think I pasted the shotgunner attack or ssomething). It's fairly simple, actor is the demon in question and target is the target (player or another monster). You need to know a bit of programming, but essentially if(!actor->target) return; means that if there is no target then the function is over and no attack occurs. The next function call is to A_FaceTarget() which makes the actor (the demon) face the target. Simple enough. The next if statement calls P_CheckMeleeRange() which will return true if the actor is within the proper range of the target so that the melee attack can land. Once that is true it sets the damage to a random amount (within a range of course) and calls P_DamageMobj directly to the target (actor->target).

So, the only way for two demons to attack each other is if one somehow gets another set as its target. That said, demons CAN miss their attacks if the player is partially invisible (I just tried it), but I believe when the player is partially invisible the attacker's angle is altered on a random basis slightly and melee attacks (due to the nature of above said function) won't damage anything else aside from their target, which, as I said, is the player or another monster that previously provoked the demon. So then CheckMeleeRange will return false (since it checks for range as well as angle, otherwise an active demon could attack you while his back is to you) and no damage will ever be applied/set.

Of course the Doom source is fairly large and complex and as with any program there are always weird things that happen, so it's still possible. Of course anyone with better source knowledge can feel free to correct me if something looks wrong.

[SargeBaldy2000]

I once encountered a similarly strange error in Map22 of Requiem. One of the arachnotron refuses to attack you, and only attacks your enemies. After a while I got scared and killed it tho heheh.

cph explained this error to me as being a result of the level lump being one byte too short (don't ask me how that would cause the error tho)

[myk]

I have never seen Demons or Spectres attacking each other, and I doubt it can happen in v1.9. Maybe the reports are true, but maybe they are based on an earlier version of DOOM.

[Nanami]

Cyb said:

Cyberdemons aren't hurt by any sort of splash damage, including barrels, so it's impossible to get them to fight short of turning on monster infighting (as far as I know anyway, I may be wrong about the barrel thing).

I'm pretty sure that's right. For a level I did recently, I used barrels to create corpses of monsters in a room. This method can be used to create corpses of monsters that you can't normally place (Hell Knight, Arch-Vile). I tried doing this with a Cyberdemon and I placed over 800 barrels and he didn't even seem phased. Also, it's worth noting that it didn't work with the Spider Mastermind either, but it did with the Arachnotron. I guess it's just the bosses that are uneffected by barrels.

And with the demons biting eachother, I think deathz0r had a screenshot of it and he said it happened when he was using IDCLIP, but I've never gotten it to work.