Neo, I don't think any of your AI's will ever finish thinking. If we say 20 possible moves a turn (and that's an underestimation), then the computer should go trou 20^10 = 10240000000000 combinations for the easy mode. Instead I think you should go fully trou a 2-5 moves, from there cut off those that seem dumb (and that's the real task), and continue with fewer. For each move, cut off those that makes less sense. In this way the computer can think a good way forward. But some of these AI pages probably say something more detailed.