Bishop & Knight Checkmate
White to play and win
PlayThe hardest elementary mate: the king can only be mated in a corner of your bishop's color, and the famous W-manoeuvre of the knight escorts it there.
No signup needed. The opponent never gives up, and every mistake gets explained.
Bishop & Knight Checkmate
Win against perfect defense
Setting up the board…
The theory
Grandmasters have failed to mate with bishop and knight. It is the only elementary mate with a genuine algorithm to learn, and the 50-move rule is a real opponent here.
Three phases. (1) Drive the king to the edge, any edge. (2) The defender will camp in the *wrong* corner (opposite your bishop's color) where no mate exists: escort it along the edge toward the right corner. This is where the knight walks its famous W shape, sealing each escape square in turn. (3) The final cage: king takes the knight's-move square, bishop delivers along the diagonal.
Why it fails over the board. One imprecise knight move lets the king slip back to the center and costs 10+ moves; against the 50-move rule, often the whole win. The tablebase defender in this drill plays the maximum-resistance defense: if your W is sloppy, you will feel it immediately.