The network needs to be told the rules of the game first, and after that, it learns by playing games against itself. That training took some 13 days for the game of Go, but just 9 hours for chess. After that, it didn't take long for it to start beating other computer programs that were already experts at those games. For example, at shogi, AlphaZero took only two hours to start beating another program called Elmo. In fact, in a blog item, DeepMind boasts that the AI is "the strongest player in history" for chess, shogi, and Go. This same algorithm could be used to play other "full information" games, like the game of hex, with "no problem," Schrittwieser says.