AI in MMORPG games

I should say that early SWG had some interesting animal behavior too! I suspect it had more to do with clever scripting than any meaningful AI but different creatures would have their own individual and social behaviors. There were cats that would stalk you for a long time before pouncing, and they were damn scarey - seeing one or two of them on your trail was as intense as the actual fighting (or sitting there and getting killed, more likely). Other beasties would walk around with their young trailing behind. Some had lookouts that would warn the pack. There were even creatures, I believe I really saw this, who would recognise when a fellow beast was dead and seem to react with sorrow or rage.

SWG now is fairly lobotomized these days. I took a run from the Rebel starport on Rori to the old original site of our player city for nostalgic reasons not too long ago. Back in the day, this was a trial. No vehicles, no shuttleports and lots of smart creatures. A ranger (once they got mask scent working) could pull it off with luck but for anyone else it was a gauntlet. Massive herds of even more massive beasts thundering along and shaking the ground, cats prowling and looking for the scent of prey…the Discovery Channel could have done a special on the wildlife of Rori or any other world for that matter.

But this return trip? Hardly anything out there and what there was just wandered aimlessly around showing no real behaviors whatsoever. Even the young creatures were gone.

There’s actually some mobs in LOTRO that do what you’re asking. I don’t recall the exact location, but there is a Goblin scout type of mob who, when attacked, will instantly run off, and meander through a couple of locations where there are other goblins hanging out.

There’s also mobs that call out to other mobs when they’re low on health.

And lots of creatures (in WoW, anyway) will try to run off when they get low on health. Yeah, they’re pretty stupid about it, but still and yet they do it.

Unfortunately, none of this is really much in the way of AI in creatures, and it’s pretty rare. I agree that more varied behaviors would make things a lot more interesting.

variety is the spice of life. and individuality. I’d like to see an MMO designed by some really visionary people who have their own ideas on the concept of an MMO. Not just “lets do it like WOW”.

Guild Wars had some major AI improvements, like enemies running out of AoE and not suiciding on hexes, and the playerbase was enraged. They were like ‘Ohnoes, AI improvements that nerf our stupid exploitive PvE farming builds! We will ragequit the game and never buy an ArenaNet game again!’

Have you guys ever been in a PnP RPG where the DM played every enemy as a brilliant tactician who a.) somehow knew the party’s weaknesses and b.) knew how to exploit them? Take for instance a low-INT humanoid, like an Orc, Kobold, Bugbear, whatever. The DM would have these things flanking, feinting, and doing everything they could to avoid the classes who resisted their damage (ie the “tanks”) and get to the classes that were easy to kill (ie the squishy casters).

It’s interesting for a little bit, sure. But soon enough it gets fucking old, and it’s always hard to believe that a wild bear, or anything with a single-digit INT and/or WIS, is that enlightened to go for the most vulnerable first.

MMORPGs have to abstract things due to their scale. Because collision detection is both computationally expensive and wide open to griefing, it gets nixed. Thus things like formation and positioning need to be abstracted and reworked, because it’s very frustrating and “unfun” if every monster can phase through the heavily-armored warrior and get right to the juicy mage (see Guild Wars if you don’t believe me – enemies beeline to casters every time, and classes that could theoretically do better at taking the damage can’t do squat to stop that). Enter the “aggro” system, which abstracts the notion of intelligence. It makes a key assumption – that mobs want to kill the player that is viewed as the biggest threat at that very moment, not the biggest threat over the span of combat (like a healer) or even the most vulnerable character at the moment (like… well, a healer).

AI doesn’t belong in these games yet. Scripted fights which make for interesting tactics, (at best an exercise of all your character’s abilities, at worst an AFK-check or “sychronized swimming” session), are about as good as it’s going to get.

My personal theory is that the AI is pretty stupid in these games to maximize the number of players per CPU. When you are playing a single player game, there’s a 1:1 player to CPU ratio, but with an MMO, the more players you can stuff on a server the higher your profit margin is.

Well the problem with GW is that there was next to no way to keep enemies inside those AoEs, which made them kind of pointless. The strongest AoEs were channeled things that did damage over time, like WoW’s Blizzard or Rain of Fire spells. Sure, there was stuff like D&D’s Fireball, but those were relatively weak.

Of course, magical DPS and class balance is so fucked up in GW that it’s almost shameful. Why a MUCH more survivable Warrior can do more damage auto-attacking than a Mage spamming spells is way beyond me.

I’d agree MMOs aren’t ready for good AI yet and don’t need it either, just yet. The assumption seems to be that PvP is the alternative to mob-grinding for people who want a more tactical experience.

But there’s a part of me that agrees with cliffski. It’s not, for me, about tactical variations and teaching people how to use their combat abilities in the most flexible manner possible, though that’s a strongpoint of good AI - it reduces predictability, or at least offers players pause that something unpredictable might happen, and makes for a more lively experience.

Are the rotes and katas, the marching drills, players go through during a big boss fight anything like the kind of tactical thinking on their feet the heroes we’re supposed to be emulating would experience? Do adventures in convential MMOs ever approach a feeling of actual adventure where one is facing the unknown? Or do we go in, headsets and mics on, with our Brady guides opened to the appropriate page for the hymn of the day?

There’s also, for me, the sense of immersion. The creatures in early SWG may have had just as predictable, and manipulatable, combat AI as a kobold in WoW but they also had that plethora of non-combat mannerisms and quirks that helped me to believe I was actually seeing exotic creatures going about their business. If they’d brought that kind of passion and vision to the recreation of the actual Star Wars setting, my god, we’d be talking about a different game and a different commercial outcome today.

Run? All the time. With enough HP to make it out of range? What the hell does that mean? Games (MMO or single player) are designed so that the player is able to beat most foes. Unless enemies somehow become faster than the player, how would they get away once they know they’re behind? It’s not like the PC is immobile.

have you ever had an enemy move back from you to summon help from his friends?

Move back? No. Summon friends? All the time. It’s led to my death more than once, as more friends have been called than I could handle.

have you ever had an enemy run for cover, or to higher ground when he sense your approach?

I don’t know how many MMOs implement cover or bonuses to higher ground, period. It’s too easy to exploit, for one.

or seen them actively keep outside your weapons range?

Yup. Ranged attack mobs in WoW will frequently try to back up. Though that’s more to use their range than thwart mine. For melee/melee, what option is there? They either keep out of your range (and can’t attack), or they get hit. Not to mention, that the PC is still mobile. Melee mobs will “luck” into good strategy against ranged PCs by charging them. Of course, there’s a buttload of skills to help ranged PCs keep mobs at bay.

Despuite huge mega advances in graphics, MMOs seem to have AI entities with the brains of planks of wood. Why? It’s not like the require AI is rocket science I speak as an ex-AI coder myself.

Well, then you should bang out an AI over the weekend and mail it off to the MMO designer of your choice. It’s just that easy!

Am I missing something here? or has everyone just got used to the fact that MMO AI is shit?

You’re missing something.

Every MMo seems to be the same. lots of stationary, or prdictable NPCs, and player characters that run everywhere all the time.
Every MMo seems to have some kind of permenant tooltip for everyone in the world telling me their name, which just helps to ruin the immersion even mroe. Do I really give a toss what the name of orc opponent #331 is?
I’m annoyed by it because I really want MMOs to be good fun, and they seem to fail so obviously and tragically.

Well, WoW doesn’t bother naming generic foes. In fact, if a mob has a name, it’s usually tougher and a leader type. There are plenty of mobs that don’t just stand around, that move on patrols or cover routes for a particular reason.

What it sounds like you want isn’t for MMOs to be good fun, but for MMOs to be specific environment you like. Pretty good odds that they’ll succeed at pleasing you specifically, since that’s not their goal.

nobody is asking for deep-blue style AI. just get characters to have more than 1 idle animation and that would be an improvement.

tak a look at the NPCs in Thief 2 for an example of it being done really well.

iirc this is the explanation given by MMO devs on the state of the AI in mmorpgs. Complex AI requires more lines of code and more CPU cycles to run. Multiply the number of MOBs per player and you can see the issues as more complex AI probably requires a geometric amount more code be written, tested, maintained, and then run in memory for each MOB.

Complex graphics are rendered on the client machine which is why the graphics have advance quicker than AI.

On a side note: As mentioned EQ1 had MOBs run when they got below a certain amount of health. It was a PITA and while more realistic it was not fun chasing MOBs and I have not seen it reproduced in many games.

I would not mind seeing a slightly robust AI in MMORPGs with variable aggro range, variable aggro(like LOTRO for some critters), scout mobs, and more intelligent tactics. The stalking cats in the initial SWG was a cute feature.

Of course smarter AI would require more balance as you would have to lower HPs, Attack Values and other things for MOBs if they were smarter.

It’s kinda funny that this is one thing that turn-based/rts and mmo’s all share: the notion that the mob/creature/opponent cannot challenge a person using its native abilities and ai, but must rely on either superior numbers or superior abilities (aka ‘cheating’). Really, this is the crux of the problem in wow which is causing all the pve vs pvp pain.

How many times in an instance have you killed something, when not 20 feet away, his buddy guard is just loitering around unresponsive and out of agro range? It would be fantastic to have things like guards respond to threats, and respond according to their ‘intellect’ in situations. Instead of instances that play out like serious sam, you’d have the option of playing them out like thief - where elements like distraction, timing and subtlety could be as, or even more important, than dps…

Nicely put. That’s pretty much why I avoid MMOs now. I just don’t see the point of paying to participate in uniniteresting rote group exercises, and that’s the way most people seem to play. And when they start to bitch that you’re not playing “right” – well, that’s the nadir of gaming.

City of Heroes had some fun and varied mob behavior that kept me interested for a while, but running from one clump of mobs to another gets tiresome quickly. When my regular group started falling into a tactical rut, I would even intentionally aggro too many enemies too soon in order to keep them on their toes. What I would have given for more realistic architecture and enemy behavior in that game.

Age of Conan is the only MMORPG that I can imagine trying any time soon, because the combat sounds interesting, the art direction is stellar, and maybe, just maybe, they’ll do something interesting with enemy behavior.

I think just a bit of a random element added to the AI choices would really freshen up the gameplay. Say you didn’t change a thing about what behaviors were open to an NPC but allowed for them to happen, or not.

So every encounter with Monster X won’t play out exactly the same. As it happens now in MMOs you generally happen upon a cluster of the same kind of monsters, engage one and see what they do. Then slaughter the rest with your new formula. The initial figuring out of the monster’s abilities and reactions is the most entertaining part. The grind comes when its time to wash/rinse/repeat that battle 300 times till the exp gain is no longer worth it.

Going further, to really make the AI worth a damn you’d have to overhaul the whole combat system. In WoW you generally do not face certain death from world monsters. Instead you generally die due to mistaking the aggro radius of a group, accidentally pulling too many monsters, or some other addition to the conflict. So say we add some rather excellent thinking skills to some groups of enemies. In the end the player could probably just brute-force through the combat, ignoring whatever clever things they do.

We see this often when routine world-enemies use effects and special moves. “Oh no that guy just cut my hamstring! Oh wait, it doesn’t matter because I am going to kill him in 2 more hits.” or a caster curses/hexes/poisons you, to counter-act it is not even worth your time for the most part. On a routine enemy the mana/item/time used is generally more expensive than just letting the lame effect run its course.

I think if we leave MMOs at the “auto attack” level we will be limited in what we can do with combat and AI. We can make smarter enemies but it makes any conflict life-or-death which is not fun to grind. Otherwise we have dumb folks that are easy and reliable to plow through, but the challenge is lacking. Then we can have a blend (the best at the moment) where world-enemies are dumb and easily cleaned up, however, certain “boss” enemies have a more scripted and complex reaction set.

To really make things interesting though I think we have to push beyond ‘auto attack’. We need to retain disposable hordes too. In Half-Life I don’t complain about “grinding” Combine soldiers. This is for 2 main reasons:

  1. The combat mechanic is intrinsically fun. A direct response to a click, with fanfare and world-effect. The speakers go Pow! The muzzle flashes, the enemy takes a hit and reacts, blood splatters. This is entertaining, it is fun and has been for a long time. You feel like you are directly interacting with the world.

Ever notice how people are constantly jumping in MMOs that allow it? Standing around and not participating in your virtual world isn’t engaging. Jumping is often the only direct and non-situational action MMO players have. So they do it often. People like to feel like the virtual world they reside in reacts to their presence. When I shoot a gun in an FPS the bullet mars the wall, enemies get hit, things fall over, just the sound and weapon recoil is entertaining.

I never feel “rooted” in an MMO. Combat feels like I lock into a mini-simulation that takes place outside of the world I am playing in. This is reinforced by enemies always clipping through me, the ground, other objects. Swords still hit with 3 feet of space in between. Arrows magically find their target.

  1. I am driven. This is actually a subtle hint of “meaning” applied to my actions. The combat in half-life is fun alone. I would go around the next corner just to get into another fight. However, having an underlying story, a mystery, a goal, pushes me on two fold. This allows the players actions to reverberate in the world even further than corpses and bullet holes.

In an MMO we should forget about trying to make stories “grab” their players , for now. We cannot trick the player into thinking that this is “their” experience and the world gives a damn about them. In LotR:O there are big elaborate scenes where you are some kind of “main character” in a compelling drama but it just doesn’t work. It feels much like combat, a mini-out-of-context event that has no real meaning or permanence to the underlying mechanic.

MMOs replace the story of the world with the story of your character’s progress. Character development is the goal. You kill that next enemy for more precious exp. This works (obviously) however it is also the “goal” of grinding. Character development is more attractive than what you actually do with the character once developed. I don’t think many people would replay the instances in WoW just to “use their skills” on the monsters there. Without the “loot” (which in the WoW-end game is really just another form of leveling) there is no re-attraction to the dungeon. Every dungeon is great the first time through. It looks gorgeous, there are new enemies, new experiences. But after that is used up there is no reason to return.

Now, if we could make the combat in an MMO fun without context. If just conflict alone was fun enough to have another conflict we’d really hit something. WoW’s first 35 levels or so are one of the more entertaining gameplay experiences available because you progress so quickly that you are constantly entering new areas. There is always something to offset any boredom you might have with the combat system. Also you get somewhat new abilities (somewhat). Once it slows down it separates the dedicated (development seekers) from the fun seekers.

People end up making a decision, in my case the end of WoW was not worth the “work” (and it is work) of getting there/living it. However, games like EVE I still play because I feel a stronger drive; PvP (the majority of the combat) is intrinsically fun, and my actions change my virtual world. EVE is far from perfect though. If they could make the numerous other activities fun (mining, trading, etc) even without their greater purpose validating the time spent with them… I’d never leave EVE.

I don’t think we could make WoW’s combat always fun with just improved enemy AI. It just will not work within the system. I really don’t think there is much left to improve upon within the auto-attack system. Direct control over your character seems to be the next step. We don’t need dice to determine if we ‘can’.

The whole idea of crafting a constantly entertaining combat mechanic is what gives me cautious optimism for Age of Conan. While it probably won’t do it “the best”, if that direct link with the virtual world works technically I think players might flock to it.

On a related topic i dont see why all games (not just MMOs) allow your character to operate at 100% effectiveness with 1% health. Anyone know any exceptions?
I want my guy to limp, to drip blood, and attack slower when he is injured. Is that too much to ask?


have you EVER had an enemy retreat in an MMO when he saw he was losing, but had enough HP to make it out of range?
have you ever had an enemy move back from you to summon help from his friends?
have you ever had an enemy run for cover, or to higher ground when he sense your approach?
or seen them actively keep outside your weapons range?

The enemies in LOTRO do all of those things. Most of the humanoid enemies will retreat when they get below a certain health level. If they run across friends, they will send them to attack you. Range enemies in the game will use snare abilities to pin you in place and then back off to use their range attacks safely.


In Eternal Darkness, as your character became more injured your animations would change to indicate that (often meaning you moved slower - some characters did limp)
You have to be careful with that kind of thing though - if you become injured and have no way of healing yourself (ED had healing spells), it means if you take any damage in a situation you are immediately in a losing situation. ie: you are at a disadvantage for running away and for killing the enemy before it kills you

In Beta, SWG had a pretty nice AI system. Different creatures have fluctuating levels of anger and fear, they bolted when scared, got angrier when cornered, you had to sneak up on them, they’d take smarter paths when not frightened, etc.

But over time, most of this type of stuff falls victim to CPU load and gets removed, or removed because of player frustration. For example, players actually complain a lot over creatures fleeing. :P

So this could easily spin off into its own separate discussion, complete with talk about damage quanta and locational damage. I imagine such a system would have a buffer (armor, shield, fatigue, etc.) to soak up normal combat wear-and-tear. Once your buffer is gone, you start taking actual damage, along with a corresponding drop in combat effectiveness.

Back on topic, I would love to see something more along the lines of Thief-style combat, where a one-on-one fight is a big deal: even if you win you’re probably in bad shape, and you definitely don’t want to be around when your opponent’s backup arrives.

But as far as AI goes, no, there isn’t any. Like others have said, there are scripts, that’s it. Some of the scripts are even quite complex. But they go off the same time every fight, there are no decisions being made, no “intelligence” of any kind. This largely removes the impact of player skill from gameplay in favor of simply knowing how the encounter works, rewarding time played (and spent reading spoiler websites) instead. This is of course entirely intentional.

How do you differentiate between a “complex script” and “true AI?” Doesn’t it all boil down to variations on “if X then Y,” except that the more complex scripts there are, the more factors the AI takes into account to adjust its behavior?

Heck, I think my own behavior is just a complex series of overlapping (and sometimes mutually conflicting) “If X then Y” routines. But then, I also think I have no soooouuuullll…