It is a neural network trained, in part, against the text in the game manual.
Of course, it's considerably more complex than that in the theory and implementation. :D
Teaching ultra-intelligent AI Monopoly, though? - guaranteed robot overlords.
1. That's gotta be one helluva manual
2. Reversing the procedure to automate documentation by examining variable and method names along various code paths would be brilliant.
It's not learning to play the whole game. It's learning to cheese (in gaming parlance) the opponent. The strategy it learns is to build a warrior as fast as possible and go and attack the enemy's city. If that fails, it almost always loses. The manual gave it some hint in that direction.