Mate in 1: knight to b3
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The tactical motive
Mate in 1: find the move after which the enemy king has no escape.
Difficulty 1033 ShuffleRating — club-player level.
Black to move — find the best continuation
How to recognize this tactic
A mate in one hides among forcing checks. Run through every check you can give: does it cover all the king's escape squares, is the checking piece safe or supported, and can nothing block or capture it? If yes, that is the mate.
General method: before you move, list the forcing candidates — every check, every capture, every direct threat — and calculate those first. The solution to a tactic is almost always among them.
Position on the board
White: king c1, rook d1 h1, bishop f1 b4, pawn b2 g2 h2 a3 c3 f3 e5.
Black: king g8, rook c6 f8, bishop g6, knight c5, pawn b5 d5 a6 e6 h6 f7 g7.
12 white and 12 black pieces are on the board; the puzzle position arises after move 21.
The position in numbers
Material is level — 23 points of pieces on each side (pawn = 1, knight and bishop = 3, rook = 5, queen = 9).
The white king stands on c1, the black king on g8.
It is Black to move on move 21, with 29 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 7 pawns, Black 7. No file is fully open, so the heavy pieces have to be pried in. Half-open for Black: c.
White hold the bishop pair, an edge in open lines. The Black king has 2 empty squares to step to right now — the fewer they are, the closer a mating net.
Solution & explanation
Main line
21... Nb3#
Why it works
- Great move! knight to b3 keeps the pressure (#).
- The line ends in a forced mate in 1.
Move by move
- 21… Nb3# — knight to b3 and it is checkmate
Types in this puzzle
Knight mate
The knight lands the killing blow from its unique angle.
In a knight mate the final blow comes from the knight — the only piece whose check can never be blocked. That makes it lethal against a cramped king: only a king move or capturing the knight itself can help. The sign: the squares around the king are occupied or covered, and there is a hop from which the knight checks while staying untouchable. Bring the knight over early — it is slower than the long-range pieces, but its strike cannot be parried.
Mate in 1
Checkmate in a single move — find it.
Mate in one: the combination is over, only the final precise shot remains. The method is simple — list every check you have and test the three escapes against each: king moves, blocks, and capturing the checker. If none of them works, it is mate. The classic blunder is falling in love with the first check you see and missing the one escape hatch.
Absolute pin
A piece is pinned against its king — it cannot legally move.
An absolute pin freezes a piece on the line between its own king and your long-range attacker: moving it is simply illegal. The pattern is three units on one straight line — your bishop, rook or queen, an enemy piece, and the enemy king behind it. A pinned piece neither attacks nor defends anything: treat it as if it were off the board. Pile up on it, ideally with a pawn, because running away is against the rules.
Provenance
Derived from the Lichess puzzle database (CC0).
Verified by Stockfish at depth 20+.
Solution forcedness confirmed (verified).
Pack 006
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