Welcome to the AiGameDev.com list of the most influential AI games of all time! You’ll find video and computer games that have used artificial intelligence in innovative ways to critical acclaim, and some of them that have managed to integrate cutting-edge AI technology too…
#10
Sim City
Screenshot: A small coastal town in Sim City 1.
Released: 1989 Developer: Maxis
30 Second Pitch
SimCity is a simulation and a city-building game that spawned a best-selling series. You get a plot of land to build residences, industries and many other buildings to keep the inhabitants of your city satisfied.
Innovations in Game AI
As the first of the “Sim” series, SimCity pioneered a new form of gameplay: controlling a complex simulation.
- Each element of the city is modeled in a realistic way, using AI if necessary (particularly in the most recent versions of the game).
The emergent properties of the system are perfectly balanced to keep the player entertained.
#9
Half-Life
Screenshot: A scientist chatting with a security guard.
Released: 1998 Developer: Valve
30 Second Pitch
Half-Life is a sci-fi first-person shooter featuring Dr. Gordon Freeman, a theoretical physicist stuck inside an underground research facility when teleporting experiments go wrong unexpectedly.
Innovations in Game AI
The cut scenes are entirely interactive. A combination of scripting and AI is used to avoid interrupting the gameplay (i.e. you can use the crowbar to destroy things while being told what to do next).
An AI security guard accompanies the player through some levels early in game.
Squad AI is used effectively for the first time in the latter stages of the game.
Despite not using any revolutionary technology, the AI is very well tweaked and integrated smoothly into the storyline.
#8
Total War
Screenshot: An army in Shogun: Total War marching over the hill.
Released: 2000-2006 Developer: The Creative Assembly
30 Second Pitch
Total War is a series of games combining turn-based strategy on a Risk-like map, with real-time tactical control of battles on a 3D terrain.
Innovations in Game AI
Thousands of AI-controlled soldiers are featured for the first time in a fun and interactive game, without noticeable performance problems.
The game models the emotions of groups of soldiers, essential for simulating battles accurately. This logic is inspired by the book, The Art Of War.
The Total War engine is used on TV by the History Channel as part of the Decisive Battles series.
→ Read Flanking Total War’s AI: 11 Tricks to Conquer for Your Game.
#7
Thief
Screenshot: Two guards in a room in Thief.
Released: 1998 Developer: Looking Glass Studios
30 Second Pitch
Thief: The Dark Project is a single player stealth-based game played from a first person perspective. The main character is Garret, a master thief applying his trade in a medieval/Victorian setting.
Innovations in Game AI
The game uses an accurate sensory model, allowing the AI actors to respond realistically to light and sounds. The whole game is based around this technique.
The AI actors use audio recordings to voice their current state, letting the player understand what’s going on.
→ Read Sneaking Behind Thief’s AI: 14 Tricks to Steal for Your Game.
#6
The Sims
Screenshot: A family inside a house in The Sims.
Released: 2000 Developer: Maxis
30 Second Pitch
The Sims is a life-simulation of the daily activities of a family of virtual characters in a suburban house. The player gets to design and build the house, as well as guide these “Sims” through the day.
Innovations in Game AI
Smart objects are used to help implement the behaviors. The object specifies how each character interacts with it, which has many scalability and workflow advantages over centralized logic.
The Sims each have basic desires which drive their choice of actions.
The emotional interaction between the characters is also modeled, which allows for relationships.
→ Read Living with The Sims’ AI: 21 Tricks to Adopt for Your Game.
#5
Creatures
Screenshot: The cartoon world in Creatures.
Released: 1996 Developer: Millennium Interactive
30 Second Pitch
Creatures is an artificial life program where the user ‘hatches’ small furry animals and teaches them how to behave. These “Norms” can talk, feed themselves, and protect themselves against vicious creatures.
Innovations in Game AI
It’s the first popular application of machine learning into an interactive simulation.
Neural networks are used by the creatures to learn what to do.
The game is regarded as a breakthrough in alife research, which aims to model the behavior of creatures interacting with their environment.
→ Read Evolving with Creatures’ AI: 15 Tricks to Mutate into Your Own Game.
#4
Halo
Screenshot: Halo’s Master Chief in combat.
Released: 2001 Developer: Bungie
30 Second Pitch
Halo: Combat Evolved is a first-person shooter where the player assumes the role of the Master Chief, battling various aliens on foot or in vehicles.
Innovations in Game AI
Enemies use cover very wisely, and employ suppressive fire and grenades.
The squad situation affects the individuals, so certain enemies flee when their leader dies.
A lot of attention is paid to the little details, with enemies notably throwing back grenades or team-members responding to you bothering them.
The underlying “behavior tree” technology has become very popular in the games industry (especially since Halo 2).
→ Read Teaming Up with Halo’s AI: 42 Tricks to Assist Your Game.
#3
Façade
Screenshot: Grace and Trip talking to the player.
Released: 2005 Developer: Procedural Arts
30 Second Pitch
Façade is an interactive story where the couple is invited to the apartment of Grace and Trip, a couple who has a relationship breakdown. The player can coach them using full typed sentences.
Innovations in Game AI
The player interacts with the game by tying text into a natural language parser.
The underlying behavior language provides ways to specify the behavior of characters in terms of a dynamic story.
→ Read Chatting Up Façade’s AI: 23 Ideas to Talk Your Game Into.
#2
F.E.A.R.
Screenshot: Enemy soldiers in F.E.A.R. getting shot down.
Released: 2005 Developer: Monolith Productions
30 Second Pitch
F.E.A.R. First Encounter Assault Recon is a first-person shooter where the player helps contain supernatural phenomenon and, naturally, armies of cloned soldiers.
Innovations in Game AI
The AI uses a planner to generate context-sensitive behaviors, the first time in a mainstream game. This technology used as a reference for many studios still today.
The enemies are capable of using the environment very cleverly, finding cover behind tables, tipping bookshelves, opening doors, crashing through windows…
Squad tactics are used to great effect. The enemies perform flanking maneuvers, use suppression fire, etc.
→ Read Assaulting F.E.A.R.’s AI: 29 Tricks to Arm Your Game.
#1
Black & White
Screenshot: A creature casting a spell in Black & White.
Released: 2001 Developer: Lionhead Studios
30 Second Pitch
Black & White is a god game which includes elements of artificial life simulations and some strategy. The player rules over an island populated by various tribes, and can teach a large animal-like creature to do his/her bidding.
Innovations in Game AI
The gameplay is focused on the interaction with a large AI creature which can learn from examples, and takes reward and punishment.
The design integrates artificial life within the context of a strategy game.
The engine uses a solid AI architecture, rooted in cognitive science, known as belief-desire-intention (BDI).
Machine learning techniques such as decision trees and neural networks are used with great success.
→ More technical AI reviews of AAA games.
Comments
Comment on this article. | Show full forum thread.I've started reading a game AI book, and it lists some other games I would have thought more important then Halo at least (which has nothing revolutionary at all on Half-Life, and don't even get me started on the dumb allies you get in Halo).
They have (which are not on your list):
Ultima Underworld: The Stygian Abyss - for brand new things - NPC's in a world with AI, and the world was 3d too.
Dogz - A virtual dog! I even remember this game - good simulation, and fun too.
Tamagochi - Representing one of the first commercial uses of A-life technology (released before Creatures)
The Last Express - I'm currently playing this, a neat game, or rather interactive movie. Amazing use of a full cast of NPC's which are autonomous (and are programmed with AI and given tasks, rather then entirely scripted - leading to multiple endings and ways to do, or not do, tasks).
I don't take credit for putting up these alternatives, and they didn't have a top 10, just a historical list, but I do agree you're missing a few influential ones - although I do agree that perhaps halo is influential to AI purely for selling a lot (as much as how it's level design is influential, or its weapons, or its online play...etc), same with FEAR. I also hope the order doesn't matter, I don't think apart from the FPS's any of the influences overlap :)
So I do agree, those are all influential games in the AI department - not all as influential as each other, and most covering different areas. I'd be interested to see if Civilisation would come on a longer list if it is influential to its own genre due to its age and how well it sold, and other games might match the criteria in their respective field (that racing game which employed neural nets, and respectively high AI's in other genres).
PS: I know, I know, its a opinionated, top 10 list, which cause my kind of comments. I think perhaps it would have been cooler to do 10+ posts on each game in a series of "Influential games" with a more in-depth look at each one, I'd certainly be interested in that more then a long comment on this single post :)
I put Halo and F.E.A.R. so high up on the list of influential games for very specific reason. Both Damian Isla and Jeff Orkin (respectively) have written very extensively about their work on the AI in both those games, and the technology has inspired the whole industry.
Just from consulting, or talking to friends in other companies, many game studios are using one of these two techniques (i.e. behavior trees or a STRIPS planner, respectively). I call that influential!
I don't think I'm too far off, but hey, this list is meant to be controversial :-)
Alex
P.S.: You anticipated my master plan for in-depth weekly reviews very well! I also felt it would be of value to write about each one in more detail.
P.P.S.: Suggestions for other AI Games are very welcome... That was also part of the plan!
And I will await any further more in-depth look at these games :) and if you miss any I think that brought something new to the table or were influential, comment so that you know of them. Civilisation (+Alpha Centuri) is one series (like Sim City) which brings several influential things, although I have not played the newer ones, such as personified world leaders (with their own personalities most importantly), strategic long turn-based play which means careful planning is needed (not done for the AI in the first few games though...), and so on.
The thing that really stood out to me is half-life is the different behaviors that the different monsters displayed as well as their interactions. Monsters having different stimulus (the tentacles responding to sound) and battle plans (hounds and assassins attacked very differently from say the zombies) really made the game enjoyable.
If you can you should check out Bioshock. While I am enjoying the game for its story telling and setting (just like everyone else who comments on the game) what really stands out to me is the AI. I wouldn't call it revolutionary but it's just a very well done implementation of AI in my opinion. The enemies have very good sensory models especially for a game that isn't based around stealth and once again (like half-life) there is a good amount of variety in the behavior of different entities.
The last remainder of this is the guards patrolling between towns who occasionally attack a wolf or a bandit - or another guard if he happens to shoot them accidentally with an arrow.
Quite sad :(
System Shock 2 was influential on me at least. I'm not sure how much of a hand Ken Levine (shameless name-drop - he's the man) had in the AI side of the development of that fantastic precursor to Bioshock but irregardless i would suspect that it inspired many others to create behaviours that reinforce immersion in story focussed games. From recollection, didn't Thief use the same engine as system shock 2? The dark engine or some-such.
http://en.wikipedia.org/wiki/Seaman_%28video_game%29
I think the reaperbots mod for Quake1 was an example of revolutionary programming and the first convincing computer controlled enemy in a FPS. The guy who wrote this did the AI for Half-Life.
Games that just stunk because the NPC's were so dumb...
One of the games that at the time left an influence on me with its AI, was Unreal. The Unreal Engine was very nice because of access to unreal script, but a particular battle against a Skaarj warrior left me with a grand impression in regards to the game's AI. ^_^
Story Mode:
I was sneaking about and came upon him, a Skaarj warrior at the far end of a passage way as I rounded a corner. His back to me, I hid behind some creates that lay about. I fired my pulse pistol (only weapon I had rounds for at the time) at him with full-charge... As the shot neared, he happened to turn to my direction and seemingly notice the incoming round, for nanoseconds before impact he dove for cover behind a crate on his end of the hall. He popped up a time or two firing shots randomly in my direction, as if to flush out or get a bead his unseen assailant. I didn't respond assuming to wait for him to reset and resume patrolling. But instead he then shot up from his position and ran toward my position zig zagging! I popped up from my cover and fired wildly at him as his actions paniced me! (I had not yet fought one of these guys melee and wanted to keep it that way!) Several times he escaped my wrath as he dove and rolled out of the way while returning fire, and then getting up to resuming his advance in nearly flawless form! The action stunded me rigid for a brief moment as it was so unexpected...I fumbled to cycle my weapons to a close-quarters melee weapon and regain my composure...
/Story Mode
That experience had an influence on what I thought the SOTA(state of the art) in game AI was, as alot of FPS don't have NPC's that actually employ such combat tactics as avoiding damage via assault manuvers and using cover in that manner. The engine also made use of sound, vision, and smell for its agents that add to the immersion of the experience. That experince had set a bar that I judged many other game AIs by.
Half-Life set a few more bars because its NPC's were not all just against you the player, but had natual enemies within the game that depending of the situation took precedence over their want to kill your character. For example a Bullsquid was in closer proximity to some headhuggers. I didn't think they had seen me where I hid and observed them fighting each other. But when the Bullsquid was victorius, it came after me with ranged attack as I was indeed noticed! The humans fought the aliens over fighting me if I could get the two into proximity, then I would just clear-up the mess! ;)
The Battle Cruiser 3000 AD series made effective use of artificial neural nets to control the NPC's that ran the ship that your character commanded as well as all the other NPC's of the game I reckon.
Just my 2 cents, cheers!
And about Oblivion... It's AI (in the current state) is something that Gothic did in 2001.
I never saw anything in Halo that I didn't see in Half-Life first. At least from an AI point-of-view. HL (1 & 2) still has better AI than a lot of shooters out there, sadly.
I would give the top spot to Creatures because it really pushed the boundaries, and it really delivered on what it claimed it could do. I would give F.E.A.R. the second place for combining groundbreaking AI techniques with critical acclaim.
I hope Spore comes straight in at number 1 when it's finally released!
Yes it's pretty much the same engine (and AI) as the Thief games, so Looking Glass gets the credit on that one. To me, that engine has the best AI (in first/third person type of games) to date, because to me great/"fun" AI is defined not how it behaves during combat, but everything else (doesn't by any means mean it should totally suck in combat). I couldn't give a damn if an enemy can duck, side step and do the funky chicken while catching a grenade with its butt cheeks and at the same time shoot at me.
An immersive/good game world to be in, is one that feels as if it's going about its business, and you're thrown into it. Not running through a mine field of triggers. For that to work good the world/AI needs some core features, like robust sound propagation and sensory systems and AI visual sensory system.
Most seem to think only a stealth game would need those, which is why I find the unqiue situation of SS2 great. It wasn't a stealth game but had the great simulation subsystems because it used the same engine as Thief, and it's part of what makes the game as good as it is. (Mind you, not even stealth games like splinter cell have such a solid simulation base, even though they had years of technical advance and faster computers to be at least as good, pretty pathetic.)
Sadly Bioshock is a huge step back, simplistic audio-visual sensory systems, player centric design (a design change they admitted doing during the developement). I would have thought that if anyone would have gotten "it" it would have been them, then again when a publisher is involved bad things happen, when a publisher owns you... game over man, game over! :)
"Yes it’s pretty much the same engine (and AI) as the Thief games, so Looking Glass gets the credit on that one. "
Hehe, pretty much considering that during the majority of development both games used the same executable. Its the reason for the longer-than-usual loading times associated with both games.
Great list btw, I have to agree that Creatures should really have been the top number. I'm patiently waiting for news of Lucy ;)
They were both released in 1996 and Creatures was far more complex so you really can't blame him for picking it.
Planescape: Torment should definitely be somewhere near the top, and yet its not even on the list. So should Oblivion.
Alex talked about why Halo was up there, it is because Damian Isla (the AI programmer for Halo), wrote about AI and was very influetential in it, plus Halo 3 has complex and quite new "Pack AI" where there is a leader AI, and he has subordiantes who flee when he dies and follow his orders.
Oblivion should be up there, donno bout Planetscape, heard about it though.
Well the man himself may have done considerable work in the field of AI, the game still has crappy AI. (Note that I've only played 1 and 2, and he mentions specifically 1 so :/)
The screenshot isn't from Creatures, it's from either Creatured Adventures or Creatures Playground.
And it's norns, not norms.
-Wolf
Unreal was mentioned already, and I agree that it had wonderful AI - it made for truly realistic combat scenarios, and Unreal Tournament really expanded on it with the squad AI it used. Watching your CTF opponents provide cover and support for the flag runner while still using cover themselves is rather impressive, especially given that it was released in 1999. Indeed, different bots responded in different ways, according to preset preferences, and could be aggressive, stealthy, defensive, you name it.
And I'm sorry, but the creatures in Black and White were dumb as bricks. The AI was undoubtedly revolutionary, but it was like training retarded five-year-olds - constant baby-sitting.
and what about Republic Commando? I heard it had the best squad based AI during its time. fun game too, albeit a bit short
I think this is because your hero/characters effects has massive effects on the rest of teh player's environment, both socially and economically. For example, your alignment (good/bad) determines how the public treat you, react to you emotionally, the children follow you if they think your good along with the plethora of external exprsseions aswell.
Furthermore, Fable 2 (when it comes out) has announced some really interactive and interesting AI. For example, if you start to neglect your dog, if its injured from battle and you run away, it will limp to follow you. However, say after you've left your dog, and your in some pub drinking somewhere, you about to leave, you open the door to see blooded scratch marks over the door with a bloody trail. the people will react and produce commments "who would do such an awful thing to an animal?" etc. Alongside this, theres a dynamic real time economy aswell, where your actions affect the rest of the game world. even from simply decing to kill a street merchant, the market place could become abandoned for example.
I think from what others have said, Metal Gear and Bioshocks not too bad for AI either. and what about GTA? especially the more recent titles, implementing more sophisticated missions some entailing great AI displays from the interaction with the environment in the city.
Other than that, its great to see games like FEAR and B&W there. I'm sure there's more but i can't think of any more off the top of my head lol
hope this helps.
There are some important game titles that you left out, namely Outcast and Oblivion.
Also your list of innovations, while good, is lacking and I believe should go further to expound upon what exactly made the AI so great.
And more importantly, you might want to list what is lacking with the AI, since game developers often seem too intent on the eye candy to develop a truly innovative game experience.
I really wasn't that impressed with Half Life's so-called squad AI. Namely because a game called Outcast came out years earlier, with about as good of an enemy AI model as I've ever seen to date. Guards patrolled cities or sat around their camp, passing time. If they spotted you, they would get up and pursue you. They might signal others over to help, or pull out a horn to let others know of your presence. If you hid... underwater, or behind some good cover, they would lose track of you and begin to search around. You could see them shield their eyes from the sun as they scanned the terrain for your presence. It was all very convincing. Enemies would try to dodge your fire, and sometimes would hit each other by accident.
I would comment on Oblivion and others, but not enough time or space at the moment.
Games just aren't as sophisticated and thoughtful as I wish they were. These things seem so obvious...
Maybe the next Elder Scrolls or Fallout 3 will try that kind of improvement to AI.
It gets even worse in Fallout 3, where your companions often decide that they can't jump over a 3 inch rubble and instead take a round-the-world detour, running across Super Mutants, Enclaves and Raiders just to get to where you are. And for some reasons they don't recognize the fact that burning cars mean nu-ku-la mushrooms 3 seconds later, and charge right into piles of burning cars without a second thought.
HL had better AI than both Oblivion and Fallout 3 combined you know.
Enemy A.I. gets the job done and not much else. Plenty of behavior inconsistencies, such as becoming suddenly aware of your presence when you are hiding nearby, being able to shoot right at you and track you through heavy foliage when you can't even see their muzzle flashes, daring to drive right up to you and then getting out directly in front of your mounted machine gun (no sense of self-preservation). There are countless other examples but these are some of the worst. Also, buddies will not get into vehicles with you or even stay with you on foot.
The only things that get high marks from me are the expected: Graphics - excellent, Sound - superb, and Voice Acting, when it is during a scripted sequence, is done extremely well, though unscripted enemy chatter leaves plenty to be desired (more variety and context-sensitive dialogue would be nice).
Also, vehicle driving mechanics are crap. And don't give me the excuse that it's expected in a FPS'er, because all it means is they were to lazy and/or cheap to implement a better handling model, such as that used in Colin McRae driving games.
But what else can be said? The gun-play feels realistic and is a blast, despite not being able to wield a P90, and despite that around 90% of the weapons are useless in most situations.
But it's what happens when developers care more about release dates and marketing a product than spending the time and money to make something truly worthwhile and innovative.
As a result, I've been playing the same 3 games for 5+ years now and will not buy another game until it proves itself to be worthy of it's time.
I loved Oblivion and Fallout 3 though. They're great. I had a follower though, and he couldn't step over a curb. He ran completely back and I had to chase him so he would stop running. Then I walked up to the little step and pushed him into it until he was over it and at the exit of the subway.
Look at Golden Eye, Rainbow Six and two already featured games Half-Life and Theif.
Out of all the games however how come no one has mentioned IBM's Chess genius beating super computer Deep Blue?
The game is a sloppy rip off of Max Pain meets Half-Life, with a few parallels possibly borrowed from certain Anime series like Bubblegum Crisis 2040.
My main issue however, is with how abysmally mediocre the gameplay is, in contrast to the hype that surrounded it at release. Enemy behavior is heavily scripted and pre-planned and basic and boring. They will move from one hiding spot to another and will peek around corners or sick their gun over to shoot blindly at you, but that's about it. They do chatter to each other and appear to communicate and use strategy, but if you pay attention, the things they say are mostly random and is essentially just a smokescreen to hide the fact that it is really just basic A.I., nothing fancy or innovative.
The graphics and world are so bad though... at least Far Cry 2 looks good and is halfway fun to explore. You can't use stealth tactics at ALL in F.E.A.R, because apparently every soldier has natural night vision. At least you CAN sneak around soldiers at night in Far Cry 2.
I'm sorry to anyone who bought F.E.A.R. and likes it, but it is not going to be on my list of recommendations anytime soon.
I am not a big Halo fan but appreciate what they have done.
You're absolutely right and thanks for taking the time to read the article & title rather than scan the list!
There's definitely enough for another article of most controversial and under-rated AI games :-)
Alex
Devs know games. RTS devs know Dark Reign, Total Annihilation, and all the Warcraft games. The AI in Halo did *not* make other game devs say "whoa... that's amazing"... except maybe ones who were brand new to gaming. Sorry.
You do, however, include Half-Life, which is proper. It's just improper that it's ranked as less influential than Halo's AI.
Still... overall a pretty great list on an easy controversial subject.
Again, Halo's technology had a huge influence on developers -- particularly thanks to Bungie's behind the scenes talks. People like Griesemer, Butcher, Isla did way more for the industry than anything we learned about Half-Life 2. If nothing else, Damian Isla helped popularize behavior trees, which is a huge step forward.
Alex
"most influential"
You'll notice that even at the time that this list came out, none of these games were "recent." The newest ones were Half-Life, Halo, and FEAR.
And, for the record, I'm including Half-Life 1 as well as 2 in my pro-HL arguments. HL1 just floored me.
Another game of note: Far Cry. I don't know how much of my "wow" was the AI and how much of it was the incredible level design (exceptionally open)... so I'll leave that to you guys to discuss.
And, of course, I'll have to leave the specifics on Halo-vs-HL behind-the-scenes to you. I'm certain you're far more educated about the gaming scene than I.
I'm off to kill me some zombies!