Nine Men's Morris

Nine Men's Morris (also called Mills or Merels) is a free online board game you can play instantly against a computer opponent named Otto, no download, no account, and no waiting for another player. Place your nine pieces one at a time on the 24-point board, then start sliding them along the lines once every piece is down. Line up three of your own pieces in a row — a mill — to remove one of Otto's pieces from the board. Drop to just three pieces and you can fly to any open point instead of only an adjacent one, but drop below three and you lose. Play through 15 levels that make Otto sharper with every match, from loose opening placements to tight blocking and swinging-mill traps near the final board.

How to play Nine Men's Morris

1. Placing phase: tap any empty point on the 24-point board to place one of your nine pieces. Otto places one back after each of your turns.
2. Once all 18 pieces are down, the moving phase begins: tap one of your pieces, then tap an empty point connected to it by a line to slide it there.
3. Line up three of your own pieces in a straight line along the board — a mill — and you immediately remove one of Otto's pieces. Pieces sitting inside one of Otto's own mills are protected from removal unless every one of Otto's pieces is inside a mill.
4. Once you are down to exactly three pieces, you can "fly" a piece to any empty point on the board instead of only an adjacent one.
5. You win by reducing Otto to two pieces or leaving Otto with no legal move on its turn — and you lose the same way in reverse, so protect your own pieces as you press for mills.
6. Clear a level to unlock the next one, where Otto blocks your mill threats more reliably and reads farther ahead before moving.

Tips

• Claim the middle-ring side points early (the four points where a spoke crosses the middle square) — they touch four lines each, more than any other point on the board, giving you the most ways to threaten a mill.
• Watch for a "swinging mill": if you can slide a piece out of a completed mill and back in on your next turn, you capture a piece almost every turn Otto can't stop you.
• Before placing or moving, check whether Otto is one move from completing a mill of its own — blocking that point comes before building your own threat.
• Late in the moving phase, avoid leaving a piece as the only unprotected target next to two of your other pieces already in a mill — spread your pieces so Otto's capture options stay limited.

FAQ