How levels work

Ten levels per game

Levels 1 and 2 introduce the game, 3 to 5 add tactics, 6 and 7 are advanced, and 8 to 10 are expert challenges with stronger bots, shorter clocks or tougher starting positions. Each level starts from a fixed position, and you are assigned a side.

Opening levels

Level 1 of every game is open to everyone. Levels 2 to 7 open one at a time when you clear the level before it, in the same game: a win in Chess does not open anything in Go. You can replay any level you have opened. Premium opens all ten levels of every game in any order.

Clearing a level

Starter levels ask for one specific move, such as completing a five or delivering mate. Match levels clear only with a win: a draw, a resignation, running out of time or leaving the game fails the attempt. In Go you must win by the level's margin after komi. A failed replay never removes an earlier clear.

Clocks

Timed levels charge only your own thinking time. The clock stops while the bot is thinking and while the page is hidden.

Bots

Bots are deterministic: the same position always gets the same reply at a given level. They run in your browser in the background so the board stays responsive. In Chess the bot resigns when it stays a rook or more behind in material, which counts as your win.

Results

Every graded game shows the result, the reason, your time and what opens next. Our server replays your moves to confirm the result before it is recorded. Without an account, results last for this visit only; sign in to keep them.

Difficulty

We are measuring how many players clear each level and will tune positions, bots and clocks from that data. We will not publish claims about how few people pass a level until we have representative results.