Mate in 2: queen to d6 (f6·2)
c9-23942naming tag (square·N)Opens in the app if installed, otherwise downloads the APK.
The tactical motive
Chess960 twist: use the unusual starting setup of the pieces.
Mate in 2: the first move creates an unstoppable threat, the second delivers mate.
A fork made possible by the Chess960 piece placement.
Difficulty 1450 ShuffleRating — club-player level.
White to move — find the best continuation
How to recognize this tactic
In Chess960 the pieces start on unfamiliar squares, so tactics appear earlier and from unusual angles. Do not trust classical patterns — read the actual lines of the bishops, the rooks and the queen from where they really stand in this position.
Mate in two usually opens with a forcing move — a check, a capture or an unstoppable threat — that strips the king of squares or defenders, so the follow-up mate becomes unavoidable. Look for the first move that leaves the opponent only losing replies.
A set-up fork needs one preparing move before the fork lands — a check that drives the king onto the forking square, or a capture that lines the targets up. Find the preparation first, then the fork it makes possible.
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 f1, queen f6, rook b1 d1, bishop f4, knight h3 c6, pawn c2 g2 h2 f3 a5 b5.
Black: king d7, queen a8, rook e8 h8, bishop d4 d5, pawn g4 b6 a7 h7.
13 white and 10 black pieces are on the board; the puzzle position arises after move 25.
The position in numbers
White are ahead by 5 points of material (34 against 29; pawn = 1, knight and bishop = 3, rook = 5, queen = 9) — the tactic has to convert or outweigh that.
The white king stands on f1, the black king on d7.
It is White to move on move 25, with 51 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 6 pawns, Black 4. Files fully open (no pawns of either colour): d, e — natural highways for the rooks and queen.
Black hold the bishop pair, an edge in open lines. The White king has 0 empty squares to step to right now — the fewer they are, the closer a mating net.
Solution & explanation
Main line
25. Qd6+ Kc8 26. Qc7#
Why it works
- Best move. queen to d6 is exactly what the engine plays (#1).
- Spot on — queen to c7 (#).
- The line ends in a forced mate in 2.
- If instead Kc8, then Qc7# and it is mate.
Move by move
- 25. Qd6+ — queen to d6 with check
- Kc8 — king to c8
- 26. Qc7# — queen to c7 and it is checkmate
Types in this puzzle
Ladder mate
Two heavy pieces climb line by line, cutting off every retreat.
The ladder mate uses two heavy pieces climbing rung by rung: one cuts the king off along a line, the other checks on the next line, driving him toward the edge. It is the classic two-rook technique — check, the king retreats one rank, the other rook checks, until mate on the last rank. The only danger is the king creeping close enough to attack one of your rooks. If it does, simply slide that rook to the far side of the same line.
Setup fork
The random setup allows a fork that classical chess never sees.
A setup fork is a double attack that exists only because of the unusual starting squares — in classical chess these targets never stand side by side. Look for pairs of undefended pieces on your opponent's back rank and for squares from which a knight or pawn hits both at once. Such forks usually appear within the first moves, before the pieces disperse. In every new position, note right away which starting pieces are defended by no one.
Mate in 2
A forced checkmate in two moves.
Mate in two: your move, any reply, then the mating blow. Start with the most forcing first moves — checks and sacrifices that shrink the opponent's options to almost nothing. Against every single reply you must have a mate ready, so check them all without exception. The common failure is analyzing the pretty defense and forgetting the boring one.
About this position
These pieces come from starting position #678.
SP-678 · ThroneGuard — King on a central file (d/e) with both knights on inner files — the classic-type setup.
The king starts on d1, the rooks on b1 and h1, the queen on a1.
Castling ends where it always does: king to g1 and rook to f1 on the short side, king to c1 and rook to d1 on the long one.
The bishops stand on c1 and f1; their long diagonals reach h6 and a6 once the d- and e-pawns step aside.
One second-rank pawn starts with no defender at all: f2.
The setup belongs to the ThroneGuard family; read right to left it becomes position 470.
The engine's main line opens with e4, putting a pawn straight into the centre.
Morozov Balance Index: 13 of 100 — class D — largest edge. Engine evaluation of the starting position: +41 centipawns for White (depth 45, 400 000 000 nodes).
Explore position #678Provenance
Mined from the project's engine self-play games.
Pack 011 · SP-678
Similar puzzles
In your browser or in the Android app. Nothing to install · Free, no ads