Mob AI - should they tank/heal/interrupt/CC/etc you?

[Val the Moofia Boss]

It seems that quite often, the player(s) has a lot of agency, having access to a lot of tools and using them when appropriate like aggro/taunting to force the enemy to attack a certain target (be it an actual mechanic, or just placing a durable character so that he is the nearest target to the enemy/bodyblocking their path so that the enemy can't go after squishies), healing (when was the last time you saw a mob healing fellow mobs fulltime?), interrupt enemy casts, CCing troublesome adds, activating defensive abilities during a high incoming damage phase, etc. But the mobs get no such agency. They never use a taunt mechanic to force your characters to attack the wrong target while the high priority mobs like threatening spellcasters are left unmolested. They don't have a fulltime healer trying to keep the other mobs alive. They don't choose to go after your squishy spellcasters or healers and try to CC or interrupt them. They don't use defensive abilities when you begin using your super powerful attacks. Etc. This is most obvious when facing other people, not dumb monsters.

Now I am saying that mobs should be programmed to be so smart that they will win no matter what like that AI program that beat the top world chess players. Videogames are meant to be beaten by the human customers. But how do you go about making this more engaging and immersive?

[rusty_shackleford]

Yes.
I'd suggest playing the divinity original sin games on the tacticool difficulty, it's the only RPGs where I felt like the AI wasn't braindead.

I never see anyone discuss it, perhaps because most didn't pick tacticool difficulty?

[edit] this is hyperbole but they're two games where I feel the AI is actually using the same rules as me, rather than simplified or alternative rules. And it's cool to see AI get creative.

[J1M]

Monsters should have roles, just as players have them. The roles shouldn't be the same as the player roles. Some roles are fun to play and others are fun to play against.

When a monster's actions appear random it isn't fun to engage with. Players like being able to predict or at least eliminate possibilities for what the monster will do, so they can feel smart for countering them.

I think you see two problems for achieving this. First, a lack of funding or effort going into the enemy behaviors compared to things like artwork. Second, teams creating scripts for monsters that have player roles, and finding it isn't fun to play against those and abandoning the idea due to a misdiagnosis of the problem.

Sometimes you see really clumsy efforts at this, like a monster that makes everyone else immune until it is killed. That doesn't give players any agency in how to solve the problem, so that doesn't work either.

[J1M]

Maybe it would be interesting to discuss which roles are fun to play vs. play against.

For example:
Glass cannon is not fun to play against. If you get hit it feels unfair (often due to not seeing the glass cannon given other things going on), if you close the distance to attack you either kill the enemy or they evade and you are reset to the start of the engagement. But when a player masters the ability to evade it can create a flow state as they snipe enemies and slip out of trouble.

Lurker is fun to play as for some people but overall not something I'd base a game around since it is mostly waiting, and fun to play against if there are visual cues and a massive damage bonus for attacking the lurker before it springs upon you.

[rusty_shackleford]

This kind of behavior also tends to come up when you fight other adventuring parties which also tend to be the most memorable encounters.

Enemy AI should probably be some function of enemy intelligence. Creatures that can't communicate having at most basic pack behavior etc.,
Highly intelligent hive minds able to work as a single whole should be some of the hardest fights you can encounter, like say, a mindflayer colony.

[ArcaneLurker]

Yes.
I'd suggest playing the divinity original sin games on the tacticool difficulty, it's the only RPGs where I felt like the AI wasn't braindead.

I never see anyone discuss it, perhaps because most didn't pick tacticool difficulty?

Have you played Troubleshooters?

[rusty_shackleford]

Yes.
I'd suggest playing the divinity original sin games on the tacticool difficulty, it's the only RPGs where I felt like the AI wasn't braindead.

I never see anyone discuss it, perhaps because most didn't pick tacticool difficulty?

Have you played Troubleshooters?

Yes but I did not care for the story to get very far.

[rusty_shackleford]

Yes.
I'd suggest playing the divinity original sin games on the tacticool difficulty, it's the only RPGs where I felt like the AI wasn't braindead.

I never see anyone discuss it, perhaps because most didn't pick tacticool difficulty?

[edit] this is hyperbole but they're two games where I feel the AI is actually using the same rules as me, rather than simplified or alternative rules. And it's cool to see AI get creative.

I could probably write an article on how goal based design influenced the DOS games.
You even see it come up in the combat: enemies pick a goal and then reason how to get to that goal.
So you'll see them do things like throwing water flasks to dilute the poison surface under an undead enemy so it stops healing(poison heals undead.). The AI is given a goal to do damage and reasoned that removing the surface under an enemy which causes recovery each turn + can be walked thru for recovery is overall more 'damage' than any other action they could take for the same AP.


(this example is something I saw the enemy AI actually do vs me and was memorable, I was not expecting the AI to realize how to counter such a tactic. Making AI memorable is arguably the most important part of AI design e.g., FEAR's AI is memorable for its verbal cues)

[Classix]

I've always liked the idea of some mob I'm fighting being able to emote to me in the midst of combat singling me out:

Veteran Death Guard taunts and points at you

" Me and you Hero... Let's see how strong your Light is against me..."

Enemy gains a buff causing party members to deal next to nothing to them and causing heals on you to not work until you engage them solo for a certain amount of time/deal a certain amount of damage and their morale or Will breaks dropping the buff. A mini 'duel' sort of. Wouldn't work in a number of things thinking about it ( mechanically ) especially depending on your class, but as a tank and PvPer I'd like the idea of a one on one with a confident enemy for a bit, would make a cool thing to witness at least if done right.

[anvi]

Everquest already does some of that. I think it possibly has the best AI in any RPG, but mostly because games have bad AI.

There are healer mobs that stay back and heal, in Ruins of Paineel there are mobs that can Complete Heal and they will heal their buddies through a wall. So you can end up screwed fighting something that keeps getting topped up and you don't even know where the healer is. Even in the low levels like Orc Camp 1 or 2 in Commonlands, the Warrior orcs will charge at you but there will be Shaman and Ranger Orcs who stay back and shoot you.

The mobs will hit people on low health too and try to finish them off, and hit anyone who sits down. There are some that can stun you really badly, and some that use charm/mez like the Ghoul Sage and some others.

They don't use defensive disciplines though, that would be cool. And taunt would too, having a warrior mob taunt a cleric or wizard or something and try to take them out would be good. They also mostly only react based on maths. Each action a player does has some aggro attached, so a big nuke or heal will generate aggro. But it would be nice if mobs could aggro players based on their role too.

It might get tiresome to have mobs constantly beating up wizzies and healers but there should at least be some that try it. And the players have taunt and stuns and heals to solve it.

I always hated how raid mobs got the more advanced mechanics. Raiding is boring and time consuming as hell. There was a great custom server which had lots of good 6 man group dungeons with raid type mechanics.

[rusty_shackleford]

Everquest already does some of that. I think it possibly has the best AI in any RPG, but mostly because games have bad AI.

There are healer mobs that stay back and heal, in Ruins of Paineel there are mobs that can Complete Heal and they will heal their buddies through a wall. So you can end up screwed fighting something that keeps getting topped up and you don't even know where the healer is. Even in the low levels like Orc Camp 1 or 2 in Commonlands, the Warrior orcs will charge at you but there will be Shaman and Ranger Orcs who stay back and shoot you.

The mobs will hit people on low health too and try to finish them off, and hit anyone who sits down. There are some that can stun you really badly, and some that use charm/mez like the Ghoul Sage and some others.

They don't use defensive disciplines though, that would be cool. And taunt would too, having a warrior mob taunt a cleric or wizard or something and try to take them out would be good. They also mostly only react based on maths. Each action a player does has some aggro attached, so a big nuke or heal will generate aggro. But it would be nice if mobs could aggro players based on their role too.

It might get tiresome to have mobs constantly beating up wizzies and healers but there should at least be some that try it. And the players have taunt and stuns and heals to solve it.

I always hated how raid mobs got the more advanced mechanics. Raiding is boring and time consuming as hell. There was a great custom server which had lots of good 6 man group dungeons with raid type mechanics.

Not going to go dig it up, but Brad purposely designed NPCs in Everquest to be like players, which is why you trade with them, talk to them using chat, etc., Other MMOs don't do this and it's such a letdown.
Crazy how advanced EQ still is in a lot of areas, I assume most devs have just never played it and assume WoW is just EQ 2.0(it's not!)

[anvi]

Yeah that's very cool. It should be checked out by any decent developer, so much to learn from it. I don't usually notice AI in games, but EQ did set a high bar that make things I've played since seem weak.

The only other game I remember being impressed by AI was STALKER. That was awesome. I hid in a house and 3 of them assaulted the house, threw a grenade in that nearly got me. I ran out the back door and down a hill and ran in a big loop and came up behind the 3 guys and got them back. And they didn't notice me which is awesome... Most games the AI reacts based on proximity, but STALKER they can see/hear and have to spot you. I remember sniping someone from out a window in a huge building like an abandoned apartment block. And I saw bad guys running towards the building. I figured they would take a while to find a way in. Nearly peed myself when I turned around and they had come in the building and up all the stairs and opened the door to my room.

[Norfleet]

It seems that quite often, the player(s) has a lot of agency, having access to a lot of tools and using them when appropriate like aggro/taunting to force the enemy to attack a certain target (be it an actual mechanic)

Doesn't really exist against a player, you see. This kind of thing pretty much DIES in a symmetrical environment where both sides consist of "intelligent" actors that are able to direct their attacks freely. Unless your combat is basically a frontarchy where players are essentially forced to attack the first object in the line, and your "aggro" system is basically just changing who is presented at the first in line, trying to force players to attack a specific target won't really work. Thus, tanking like that vanishes entirely since neither players nor properly functioning AI are really able to be manipulated like this. If you can block them into a certain target, you won't be able to stop them from reserving their good limited attacks for nuking the proper target.

or just placing a durable character so that he is the nearest target to the enemy/bodyblocking their path so that the enemy can't go after squishies)

Generally a more "realistic" means of doing things that remains stable even with an upgraded AI.

healing (when was the last time you saw a mob healing fellow mobs fulltime?)

They exist. If anything, it's one of the easier tasks for an uncomplicated AI to do. Healbots are often the favored form of NPC companion for players, so there's no reason that enemies can't also have their own healbots.

interrupt enemy casts

If it's possible to do this, NPCs tend to already do it.

CCing troublesome adds

Players generally don't have access to infinite add/pet spam the way enemies do, so enemies don't really need to think about doing this.

They never use a taunt mechanic to force your characters to attack the wrong target

Because players won't really comply. They either simply won't move in the desired direction to even do so, and thus just ignore it, or won't use their actual good abilities. "Taunt Mechanics" exist because the AI has no deeper targeting logic and the battle system is rarely designed for symmetric play. You just don't see this kind of thing in a PvP game because both sides are symmetrical, and similarly, they make no sense if it's a PvP game where one side is AI.

while the high priority mobs like threatening spellcasters are left unmolested.

Well, if you want an AI that's smart, it'll always try to focus down the target with the highest rate of threateningness to squishiness. The catch being that assessing this is tricky for an AI given the weird **** players can build. If you simply bias the results towards favoring attacking specific classes of players, you end up with hilarious "TankMage" builds, where the players exploit the fact that the AI is overweighting a factor like "character class" independently of build, so somebody makes a TankMage that twists the entire build to be about durability above all, and then when the AI sees "a wizard, we must squish it", they're sucked into aggroing a TankMage that has sacrificed its actual ability to be a threatening spellcaster for its ability to be an invulnerable brick.

They don't have a fulltime healer trying to keep the other mobs alive.

As I said, this is probably the most common thing TO exist. WAY too many raids have a design where a boss is being buffed and supported by some attendants that the party generally must kill to make the boss defeatable.

They don't choose to go after your squishy spellcasters or healers

This requires that the AI be able to identify a "squishy spellcaster or healer" first, and NOT end up chasing a Kite or Tank Mage.

and try to CC or interrupt them.

No one likes CC spam. It's not fun. Games that have it tend to inevitably see their PvP systems decline and fail because uncounterable CC spam isn't enjoyable to play against. If it CAN be countered, then pretty much every player will end up running immunities to it, rendering the point moot. In fact, the only reason these kinds of abilities tend to exist in the game at all, is because of the fundamental asymmetry between player parties and NPC enemies: Players are few in number and being mobbed by, well, mobs, of mobs.

This is most obvious when facing other people, not dumb monsters.

Games with PvE-centric design always have terrible PvP for this reason. You cannot name ONE game where you have a PvE design like this, and you can take a character in that game and just take it into the game's PvP venue and expect to succeed. The game's PvP mode is functionally a separate, unrelated game for this reason, and thus will always suffer from being of reduced popularity at best, and outright unpopular to abandoned at worst.

Now I am saying that mobs should be programmed to be so smart that they will win no matter what like that AI program that beat the top world chess players. Videogames are meant to be beaten by the human customers. But how do you go about making this more engaging and immersive?

The thing is, a large number of people seem to actually prefer things this way. But if you want to make the game more engaging and immersive, start with symmetrically-oriented design. Assume you are making a PvP game where the other side will be played by humans. Then replace them with bots that, like the humans they replaced, are playing to win, with both sides playing by the same rules. Not rules like "A player unit has a thousand hitpoints, but the exact same unit in NPC hands has a million hitpoints": If a human knight or a T-34/85 has some stats when operated by a player, the NPC version should be exactly the same, obeying the same rules and limitations. Obviously, this does not apply when the player fights non-peer adversaries such as beasts or monsters, so people who want non-symmetric fights can go fight a bear or a dragon or something.

Once you have what the AI *SHOULD* be doing, you can then adjust it to account for the limitations of the exact critter it's simulating. Orcs, for instance, are not generally terribly bright, so do not make full use of the AI or introduce biases to the system, thus making an enemy Orc Infantryman perform tactically worse than a Human Infantryman, even though their stats are roughly the same. The player will then feel these differences all that much more acutely, and see the difference between Throg's Raiders and Soldiers of the Marquis not because "one has 10x the stats because they're higher level", but because one is a bunch of angry green bois and the other is a bunch of professional soldiers.

[rusty_shackleford]

In lineage 2's pvp you could taunt other players which caused their active target to change to the person that taunted him. As the game played out in real-time, people who got taunted the most were healers afaik. In a turn-based environment you'd need some sort of forced-targeting in response to a taunt. Even in real-time, perhaps a small lock-on period would be adequate.
I last played a long time ago so my memory might be wrong.

[Kalarion]

Surprised no one has mentioned KotC2 yet.

On the one hand Mr. Rootman did a bang-up job putting together the AI, it was absolutely brutal.

On the other hand, feeding into J1M's point, it's not usually fun to go up against a near-human set of priorities when the game is rocket tag. Instead of an interesting encounter you end up with Edge of Tomorrow until you've found the perfect combination of grinding, setup, initiative dominance and AI quirk to allow you to nuke the entire map in the first round. That may sound fun in abstract, but based on my reading of the KotC2 release thread, it got old and aggravating and exhausting really fast.

[Norfleet]

On the other hand, feeding into J1M's point, it's not usually fun to go up against a near-human set of priorities when the game is rocket tag.

Rocket Tag is generally not a fun game to be playing at all in a perfect-information environment like the typical RPG. You can't really have interesting Rocket Tag gameplay in a situation of "everybody sees basically everybody with few exceptions". Any kind of rocket-tag gameplay is going to be either extremely twitchy, extremely stealth-based, or extremely boring, in some combination thereof.

[J1M]

On the other hand, feeding into J1M's point, it's not usually fun to go up against a near-human set of priorities when the game is rocket tag.

Rocket Tag is generally not a fun game to be playing at all in a perfect-information environment like the typical RPG. You can't really have interesting Rocket Tag gameplay in a situation of "everybody sees basically everybody with few exceptions". Any kind of rocket-tag gameplay is going to be either extremely twitchy, extremely stealth-based, or extremely boring, in some combination thereof.

There's a game called Nerf Arena that reskinned Quake II(?) with Nerf guns that is actually quite fun. There are targets worth points that you can shoot throughout the levels that add another dimension to deathmatch or deathmatch-adjacent maps. The alternate objectives take the edge off of the gameplay spiral you are referring to. I wouldn't be surprised if Splatoon owes some of its success to that game.

[Norfleet]

There's a game called Nerf Arena that reskinned Quake II(?) with Nerf guns that is actually quite fun. There are targets worth points that you can shoot throughout the levels that add another dimension to deathmatch or deathmatch-adjacent maps. The alternate objectives take the edge off of the gameplay spiral you are referring to. I wouldn't be surprised if Splatoon owes some of its success to that game.

I mean, nobody said Quake was boring, but you can't deny that's clearly heavily twitch-based. Your mentioned attempts to reduce that seem more aimed at attacking the rocket tag nature of the game rather than finding a way for rocket tag to escape what I said.

[WrenchWring]

It depends on how smart the mob is supposed to be. It's more important that the enemies play their roles properly than it is for them to play optimally. Goblins, skeletons, giant rats, shouldn't be smart enough to prioritize targets and should just rush whatever's closest. Smarter enemies like professional soldiers or evil wizards should be prioritizing vulnerable targets, applying CC, etc. I'd also consider occasionally heavily scripting a few important named characters to make them behave in specific ways in combat. If this one evil wizard is obsessed with poison gas, he should be spamming poison gas clouds in combat. Characters should continue to be characters when combat starts.