[Houshalter]

The thing is most simple game AI isn't challenging. Or it's challenging in boring ways. Like having 100% perfect aim or long health bars. It's awesome to have an AI that is challenging by actually being good at the game. Having some actual strategy and intelligence.

It's a complete misconception that "real AI" needs to be super hard. Give it realistic constraints like slow reaction times or noisy input. You can handicap it in many ways to control the difficulty. Modern chess engines can easily beat even the best players in the world. But by limiting the number of moves they search, you can set one up that new players can beat.

My favorite game AI is from age of empires 2. All other RTSes just let the AI cheat like crazy to provide challenge. For AoE2 they went to a lot of work to design an expert system and a custom scripting language for it. Tons of features were implemented to make it easy to write relatively sophisticated AI strategies. And they documented it well and made it easy for modders to write even better AI scripts.

As a result the AI on hardest can beat all but skilled competitive players without cheating at all (at least the current AI shipped with the steam version.) It's actually fun to play against and isn't a terrible substitute for a real human player.

[krasi0]

Similarly to that, there exist AIs for Starcraft Broodwar that are capable of providing a decent challenge to novice and intermediate level human players. You could check some examples at play on: http://sscaitournament.com/ and also develop your own AI in one of the more popular programming languages (C++, Java, etc). Disclaimer: I am the author of one of those Starcraft Broodwar AIs