Openings › Mate in one › December 2025 › Exercise 3 of 4
Mate in one: White to move (exercise m1-6d1a0e4bea)
White to move and mate in one. In this position White can give checkmate with one move. The position comes from a rated Lichess game of December 2025.
Last move: 31…Kd4 (Black's king from e5 to d4); its two squares are marked on the board.
Pick a piece, then its square. Keyboard: Tab to the board, arrow keys to move, Enter or Space to pick.
Hint 1: which piece?
Look for a pawn move.
Hint 2: which square?
The mating move goes to c3.
Show the solution
One move gives checkmate:
- c3# (c2 to c3). After this move, the white pawn on c3 gives check to the black king on d4, and Black has no legal move: checkmate. The black king on d4 has no safe square to go to (c3, c4, c5, d3, d5, e3, e4 and e5). Its own pawn on c5 stands in the way. c4 is covered by the white bishop on d5. d3 is covered by the white king on e2. e3 is covered by the white king on e2 and the white bishop on f4. e5 is covered by the white bishop on f4. The king may not take the white bishop on d5: the white pawn on e4 guards d5. The king may not take the white pawn on e4: the white bishop on d5 guards e4. The white pawn on c3 cannot be captured: the king may not take it, as the white pawn on b2 guards c3. The white pawn on c3 stands right next to the king, so nothing can be put in between.
Our code tried every legal move of White in this position: this is the only move that gives checkmate.
The position as text
- White to move.
- Last move: 31…Kd4.
- White: king e2; bishops d5, f4; pawns a2, b2, c2, e4, g3, h2.
- Black: king d4; bishop b6; pawns a7, c5, h6.
- Castling: no longer allowed for either side.
- FEN:
8/p7/1b5p/2pB4/3kPB2/6P1/PPP1K2P/8 w - - 3 32
Where this exercise comes from
The position comes from a rated game in our sample of the Lichess open database (CC0 1.0), from the monthly file of December 2025. From a game that began with the Englund Gambit. In that game White gave checkmate with the next move. We show no player names and no link to the game. Our code tried every legal move of the position and lists every move that gives checkmate; the list, the hints and the explanations are checked again each time the site is built. How the exercises are chosen: Mate in one and How it works.