Mate in 3: knight to f7 (d6·3)
c9-26669naming 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 3: a forced sequence that ends in checkmate.
A fork made possible by the Chess960 piece placement.
Difficulty 1630 ShuffleRating — for advanced tacticians.
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.
In a mate in three every move must be forcing; the defender should never get a free tempo. Find the check or threat that herds the king, calculate the single defence to each, and confirm the net closes on the third move.
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 e1, rook f1 a2, bishop d2 d5, knight d6, pawn h2 e3 a4 b4 d4 h5.
Black: king h8, rook d8, bishop c7, pawn e4 b5 a7 d7 g7 h7.
12 white and 9 black pieces are on the board; the puzzle position arises after move 28.
The position in numbers
White are ahead by 11 points of material (25 against 14; pawn = 1, knight and bishop = 3, rook = 5, queen = 9) — the tactic has to convert or outweigh that.
The white king stands on e1, the black king on h8.
It is White to move on move 28, with 40 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 6 pawns, Black 6. Files fully open (no pawns of either colour): c, f — natural highways for the rooks and queen. Half-open for White: g.
White hold the bishop pair, an edge in open lines. The White king has 3 empty squares to step to right now — the fewer they are, the closer a mating net.
Solution & explanation
Main line
28. Nf7+ Kg8 29. Nxd8+ Kh8 30. Rf8#
Why it works
- Great move! knight to f7 keeps the pressure (#2).
- Spot on — knight to d8 (#1).
- Precise: rook to f8 is the top choice (#).
- The line ends in a forced mate in 3.
- If instead Kg8, then Nxd8+ and you win the rook.
Move by move
- 28. Nf7+ — knight to f7 with check
- Kg8 — king to g8
- 29. Nxd8+ — knight to d8 (capture) with check
- Kh8 — king to h8
- 30. Rf8# — rook to f8 and it is checkmate
Types in this puzzle
Back-rank mate
The king is locked behind its own pawns — a heavy piece strikes the last rank.
The back-rank mate strikes a king locked behind its own unmoved pawns when a rook or queen crashes onto the last rank. The signs: no escape hole in front of the king, and the back rank guarded by a single piece or by nobody at all. Often that lone guard is deflected or traded off first, and only then comes the invasion. In your own games, make luft in time — one pawn move prevents a sudden catastrophe.
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 3
A forced checkmate in three moves.
Mate in three is a forced staircase: each of your moves narrows the opponent's choices, and the third one ends the game. Look for the start among checks and sacrifices — quiet first moves are rare in mating problems, but deliciously sneaky. Keep the tree in your head: every defense gets its own branch. Do not stop calculating after move two — see the final mating picture with your own eyes.
About this position
These pieces come from starting position #593.
SP-593 · BastionScout — King shifted to c or f, with a knight committed to the corner from move one.
The king starts on f1, the rooks on b1 and g1, the queen on c1.
Castling short simply swaps the two pieces: the king on f1 and the rook on g1 trade places.
A bishop starts in the corner on a1: it has a single diagonal, which the b-pawn unlocks, running out to h8.
The second rank carries 2 pawns with no defender at all: a2, h2.
The setup belongs to the BastionScout family; read right to left it becomes position 267.
The engine's main line opens with c4.
Morozov Balance Index: 99 of 100 — class A — most balanced. Engine evaluation of the starting position: +2 centipawns for White (depth 47, 400 000 000 nodes).
In 50 self-play games White scored 49.0% (95% CI 35.7–62.4%).
Explore position #593Provenance
Mined from the project's engine self-play games.
Pack 012 · SP-593
Similar puzzles
In your browser or in the Android app. Nothing to install · Free, no ads