There are some wonderful examples of this in tom7's videos about learnfun/playfun, an AI that (in short, very simple/stupid terms because that's all I know) in

There are some wonderful examples of this in tom7's videos about learnfun/playfun, an AI that (in short, very simple/stupid terms because that's all I know) in learnfun watches human gamepad inputs + the NES memory, and in playfun tries to provide its own inputs to make numbers in certain NES memory locations (those that went up for the human player) go up. One way to not lose is to just pause the game. Minor spoiler: learnfun figures that one out :-) http://www.cs.cmu.edu/~tom7/mario/ http://www.cs.cmu.edu/~tom7/mario/