Video game artificial intelligence is a fascinating merger between programming and artistic deception. Richard Bull, lead AI programmer for Empire: Total War explains in an interview, “the AI academics are your wizards and we’re your stage magicians—it’s all smoke and mirrors with game AI” (Ben Hardwidge, “How AI in Games Works”, bit-tech, 5 March 2009). An academic trying to simulate a human brain has a massive super computer devoted to the task of thinking, while an AI programmer for a video game is instead working with a small percentage of processor power. The majority of the computing power in games is instead going towards depicting graphics, sound, physics, and cow bell type things. For example, technically the AI in Halo 3 is less sophisticated than in Halo 2 because most of the processor has to be devoted to graphics. A giant, open world game will inherently have stupider AI because there just isn’t enough power to go around. So the art of video game AI is in making a player think that they’re interacting with something more sophisticated than it really is.
The first and most obvious technique for making an AI look smart is just keeping it alive long enough for the player to even notice it. An in depth discussion of the AI in Halo points out that the main difference between playing the game on Easy versus Legendary is that everything has more health and the player has far less (Alex J. Champanard, “Teaming Up With Halo’s AI: 42 Tricks To Assist Your Game”, AIGameDev.com, 29 October 2007). Play testers were more complimentary of an AI when they were able to observe it perform various tasks as opposed to just killing it on sight. Consistency is also an important factor, it’s important to not curve difficulty by dumbing down the machine or reducing its abilities. Once you see an AI behaving stupidly, the impression is permanent. Once a person is observing the AI, it’s also important to make sure that it’s broadcasting its conduct back to the player as much as possible. The Brutes seem smart in Halo 3 because we hear them shouting, “Flank him”, before they execute an otherwise simple AI command. Grunts seem like they’re responding to us because they shout “Run away”. Getting the player to even notice that the AI is doing something besides shoot is the first step to making it look good.