https://slatestarcodex.com/2020/01/06/a-very-unlikely-chess-game/

Turns out, you can actually train GPT-2 to play chess by just having it predict the next move, represented by a string such as “e2e4”. I don’t believe it’s even given the board state, simply the list of previous moves. By just training on this, it’s able to successfully perform opening moves/strategies and into the midgame, though longer games tend to eventually fail due to the model outputting moves that simply aren’t valid.

The author emphasizes that this was a small project done in only a few days of work, but the initial results are pretty exciting.

The linked tweets have more detail: https://twitter.com/theshawwn/status/1212272510470959105