About Santorini

Santorini is a building game: two players race to the top of the towers they build together on a little Greek island. It was designed by Gordon Hamilton and is published by Roxley. This is an unofficial fan-made version and isn't associated with the real game.

Like it? Go buy the real thing!

How to Play

Each player has two workers. To start, the first player puts both of theirs on any empty squares, then the other player does.

On your turn, move one of your workers to any of the eight squares around it. It can climb up one level at most, and step down as far as it likes. Then that same worker builds: it adds a level to a square next to where it now stands. A tower goes up three levels, then a dome caps it for good. Nobody can move onto or build on a square with a worker or a dome.

Step up onto a third level and you win. You also win if your opponent can't move.

The real game also has god powers: cards that give each player a special ability. This version plays the basic game, without them. It also never runs out of blocks, which almost never matters.

The AI

It works like DeepMind's AlphaZero. A neural network learned the game by playing itself, over five million games in about a day of training, with no human games or tips. On its turn, a tree search uses the network to size up moves and plays the best one it found.

It all runs in your browser. Expert thinks for 2 seconds a move, so it's a bit stronger on a faster device, and it first checks for a win within its next two turns, so it never misses one. The other levels don't look ahead at all. Strong plays whatever looks best right now, and each level below it picks more at random, down to Random, which plays any legal move. The Analysis page shows what it makes of any position.