Ranged Caster AI


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Lair Larrikin

Posts: 18

Joined: Friday, 3rd March 2017, 15:24

Post Monday, 27th March 2017, 19:46

Ranged Caster AI

I'm really curious about this one. I noticed in older versions of the game that monsters would sometimes run away after they were wounded, perhaps in an attempt to make things more realistic when it comes to monster behavior. But that behavior no longer exists. Also you never see situations in the dungeon where monsters are at odds with one another, so an oklob will ignore every other creature but the main character. I am guessing that the reasoning behind this could be
A) it would cause problems with someone other then the protaganist killing things thus reducing the difficulty level of the dungeon or B) it will make things harder by reducing the xp available to the character or C) introducing to much complexity is causing some other issue.

But the one behavior from mobs I've seen in the dungeon that bothers me the most that I'm surprised has not been addressed is that of ranged casters. They just seem to shuffle along and gradually move closer to the character. Its a ranged caster, why is it approaching you? Shouldn't it be trying to blast you from a distance instead of wasting auts approaching you? Why do they do this thing?

*Disclaimer, wasted tons of hours playing this game, its a good game and I think the people who have contributed to it over the years should be proud. Just asking a question.

Dungeon Master

Posts: 3618

Joined: Thursday, 23rd December 2010, 12:43

Post Monday, 27th March 2017, 20:06

Re: Ranged Caster AI

A more clever AI, especially for centaurs, has been tried. Crawl 4.1 (this is after vanilla Dungeon Crawl and before Dungeon Crawl Stone Soup) had this, for example. The main problem is that it leads to more realistic, but also a lot more annoying gameplay.

Just assume that monster centaurs could kite you: that'd imply you'd be forced to have a strong ranged attack (spell, bow/crossbow/etc., wand) by the time they appear -- which is about D:5. (The attack needs to be strong because centaurs deal reasonable damage.) Currently, you have the following options: (a) ranged damage, (b) flee, e.g. teleportation, (c) wait behind corners, (d) charge towards it.
Centaurs kiting would definitely remove option (d) and, given their AI is good enough, option (c) as well. So the game gets harder, but not in a good way.

You can see that Crawl is able to use this kind of AI in orb spiders. In general, Crawl is a game awash with monsters. Most of them should be stupid and act mindlessly. Nifty behaviour should be left to uniques or selected, rare monster classes.

If you want a game where monsters are smarter, and where this works well, try Brogue.

About monster infighting, e.g. monster elves fighting monster orcs: this sounds cool, because it supposedly makes the dungeon more lively. But in reality it makes you wait behind a corner until monsters have battled each other, and then you deal with the rest. In Crawl, you are the lone super hero, and everyone just forgets their enmities and is out to kill you. It's a very trite story, but if it's good enough for several millenia of mankind, it'll do for Crawl.

For this message the author dpeg has received thanks: 2
nago, scorpionwarrior

Lair Larrikin

Posts: 18

Joined: Friday, 3rd March 2017, 15:24

Post Monday, 27th March 2017, 20:16

Re: Ranged Caster AI

dpeg wrote:Just assume that monster centaurs could kite you: that'd imply you'd be forced to have a strong ranged attack (spell, bow/crossbow/etc., wand) by the time they appear -- which is about D:5. (The attack needs to be strong because centaurs deal reasonable damage.) Currently, you have the following options: (a) ranged damage, (b) flee, e.g. teleportation, (c) wait behind corners, (d) charge towards it.
Centaurs kiting would definitely remove option (d) and, given their AI is good enough, option (c) as well. So the game gets harder, but not in a good way.

You can see that Crawl is able to use this kind of AI in orb spiders. In general, Crawl is a game awash with monsters. Most of them should be stupid and act mindlessly. Nifty behaviour should be left to uniques or selected, rare monster classes.


The example I was thinking of is the elves. The elf branch is an optional branch (in other words can be avoided) of what you might think are highly intelligent casters but they act like dunces. Also it comes later in the game then the situation you described so the player would have more tools for handling the situation. Also if the centaurs were smarter you could just have them appear later then they do currently. I wasn't thinking all ranged attackers would exhibit this behavior, just the ones that you would expect to. I believe it would make the post lair game more interesting.

Ziggurat Zagger

Posts: 5364

Joined: Friday, 25th November 2011, 07:36

Post Tuesday, 28th March 2017, 00:15

Re: Ranged Caster AI

I think it's important that all monsters can be killed by each of the three main character types: melee, ranged combat, and magic. That is not to say that 'pure' characters are the correct way to build characters, or that they are optimal, but that it should in theory be possible for melee characters to beat everything. It is fine if certain monsters are harder for melee to kill (pretend spiny monsters hurt a lot), or certain monsters are harder for ranged to kill (say it has reflect), or harder for mages (lots of elemental resistances); it should just still be technically possible, even if it's not ideal.

For this reason, I really hate red devil's "hop backwards" ability, which is similar to what you want centaurs to do - they move backwards indefinitely while attacking. It's even worse because it does happen late in the game and the monster is rather weak for it's depth, so it's rarely ever an actual threat, but merely annoys you if you try to actually use melee on it.

Lair Larrikin

Posts: 18

Joined: Friday, 3rd March 2017, 15:24

Post Tuesday, 28th March 2017, 04:07

Re: Ranged Caster AI

You say it annoys you that the monster hops backwards. I am also annoyed by ranged attackers hopping forwards. Its like a scene out of Walker Texas Ranger.

Note that there are 3, not 2 possible main behaviors.

1) Kiting
2) Standing still, like a turret
3) Running forwards, like an idiot.

I'd like to see more of 1, but even 2 would be an improvement.

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