8
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2
a1
b
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h
The king's box: 45 squares
0/33
The idea
Side by side, the two bishops make a diagonal wall the king cannot cross; push the wall towards a corner with your king's help.
A sliding diagonal wall.
- Put the bishops next to each other in the centre: together they cover two neighbouring diagonals.
- Bring your king up to take squares the bishops cannot.
- Move the wall in, one bishop at a time, pushing the king towards the edge and then a corner.
- Mate comes in the corner with both bishops checking along neighbouring diagonals in turn.
- Watch for stalemate when the king is in the corner.
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).