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The king's box: 37 squares
0/17
The idea
The queen alone builds a cage around the king; shrink the cage one step at a time, then bring your king to help, and never leave the king without a move.
A cage that gets one row smaller with every move.
- Put the queen a knight's move from the enemy king: it takes away the most squares while staying safe.
- Follow the king with the queen, keeping that knight's-move distance, until it is stuck on an edge.
- Stop with the queen and walk your own king over: the queen cannot mate alone.
- Mate with the queen next to the king, protected by your king, or along the edge.
- Before every queen move, check the enemy king still has a move: no moves and no check is stalemate, a draw.
Press Next (or →) to watch the technique, move by move. Your side starts.
Every verdict comes from the Lichess tablebase (exact for seven pieces or fewer).