Attack on the uncastled king: queen to d6 (h2·4)
c9-26184naming 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.
Uncastled king: the enemy king is stuck in the centre — punish it before it castles.
Difficulty 1760 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.
An uncastled king in the centre is a standing target. Look for ways to open the central files and diagonals against it with checks and threats before it can shelter — every tempo the king spends in the middle is a chance for a combination.
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 a2, queen h2, rook b1 f1, pawn e4 c5 d5 b6 e6.
Black: king b8, queen g7, rook a8, bishop c2, pawn a3 d6 h6 b7.
9 white and 8 black pieces are on the board; the puzzle position arises after move 37.
The position in numbers
White are ahead by 3 points of material (24 against 21; pawn = 1, knight and bishop = 3, rook = 5, queen = 9) — the tactic has to convert or outweigh that.
The white king stands on a2, the black king on b8.
It is White to move on move 37, with 39 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 5 pawns, Black 4. Files fully open (no pawns of either colour): f, g — natural highways for the rooks and queen. Half-open for White: a, h.
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
37. Qxd6+ Kc8 38. Rf8+ Qxf8 39. Qxf8#
Why it works
- Best move. queen to d6 is exactly what the engine plays (#2).
- Spot on — rook to f8 (#1).
- Precise: queen to f8 is the top choice (#).
- The line ends in a forced mate in 3.
- If instead Kc8, then Rf8+ and you stay on top.
Move by move
- 37. Qxd6+ — queen to d6 (capture) with check
- Kc8 — king to c8
- 38. Rf8+ — rook to f8 with check
- Qxf8 — queen to f8 (capture)
- 39. Qxf8# — queen to f8 (capture) and it is checkmate
Types in this puzzle
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.
Win the pinned piece
The pinned piece cannot run — attack it again and win it.
A pinned piece cannot flee, which means you can win it outright by attacking it one more time. Count attackers against defenders: if you outnumber them, the piece is yours. The best extra attacker is a pawn, since it costs less than anything it might capture. Do not rush the capture — build up the pressure first, then harvest.
Uncastled king
The king lingered in the middle — punish the delay.
Punishing the uncastled king: your opponent delayed castling, and now his king is stuck on its starting square under fire. In Chess960 this is deadlier than in classical chess — the king may start in the center or near the edge, and the familiar defensive setups simply do not apply. The signs: the victim still holds castling rights, and the files toward his king are half-open. Open lines before the king manages to hide.
About this position
These pieces come from starting position #837.
SP-837 · RampartScout — Wing king plus a rim knight, and only 72 positions qualify — the rarest pattern of all.
The king starts on b1, the rooks on a1 and f1, the queen on g1.
From b1 the king makes the longest journey Chess960 allows when castling short: five squares to g1.
The bishops stand on c1 and d1; their long diagonals reach h6 and h5 once the d- and e-pawns step aside.
Every pawn on the second rank is defended from the very first move.
The setup belongs to the RampartScout family; read right to left it becomes position 122.
The engine's main line opens with a4.
Morozov Balance Index: 51 of 100 — class C — noticeable edge. Engine evaluation of the starting position: +26 centipawns for White (depth 47, 400 000 000 nodes).
Explore position #837Provenance
Mined from the project's engine self-play games.
Pack 013 · SP-837
Similar puzzles
In your browser or in the Android app. Nothing to install · Free, no ads