Attack on the uncastled king: bishop to c7 (b6)
c9-12778naming 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: a forcing sequence that ends the game — the king has no escape.
Mate in 4: a forced checkmate in four moves — every reply is covered.
Uncastled king: the enemy king is stuck in the centre — punish it before it castles.
Difficulty 2350 ShuffleRating — expert level — few solve it at first try.
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.
This is a forced mating attack. Start from the enemy king: which of its squares are already covered, and which move takes away the rest while keeping the king in check? Forcing moves — checks and captures — are what turn an attack into mate.
A mate in four is a longer forced net: each of your moves is a check or an irresistible threat, and the king is driven step by step to a square where it is finally trapped. Verify that the defender has exactly one reply at every branch.
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 b1, queen f2, rook a1 f1, bishop b6, knight b5, pawn b2 c2 d3 a4 g6.
Black: king b8, rook a8, bishop b7, knight c6 g8, pawn g4 a5 e5 e6 c7.
11 white and 10 black pieces are on the board; the puzzle position arises after move 24.
The position in numbers
White are ahead by 11 points of material (30 against 19; pawn = 1, knight and bishop = 3, rook = 5, queen = 9) — the tactic has to convert or outweigh that.
The white king stands on b1, the black king on b8.
It is White to move on move 24, with 45 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 5 pawns, Black 5. Files fully open (no pawns of either colour): f, h — natural highways for the rooks and queen. Half-open for White: e.
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
24. Bxc7+ Kc8 25. Qf8+ Kd7 26. Qd6+ Ke8 27. Rf8#
Why it works
- Best move. bishop to c7 is exactly what the engine plays (#2).
- Spot on — queen to f8 (#2).
- Precise: queen to d6 is the top choice (#1).
- Best move. rook to f8 is exactly what the engine plays (#).
- The line ends in a forced mate in 4.
- If instead Kc8, then Qf8+ and you stay on top.
Move by move
- 24. Bxc7+ — bishop to c7 (capture) with check
- Kc8 — king to c8
- 25. Qf8+ — queen to f8 with check
- Kd7 — king to d7
- 26. Qd6+ — queen to d6 with check
- Ke8 — king to e8
- 27. Rf8# — rook to f8 and it is checkmate
Types in this puzzle
Mate in 4+
A long forced mating combination.
Mate in four or longer is a marathon of forcing moves where the grip must never loosen. The tools are the same: checks, double threats and sacrifices that deny the opponent a single free tempo. Do not juggle the whole tree at once — walk the main line all the way to mate first, then verify the side branches. If somewhere the defender finds one quiet move that holds, your very first move was wrong.
Royal fork
A fork with check: the king must move, and the second piece is lost.
A royal fork is a fork with check — one of the two targets is the king itself. The check must be answered first, so nobody is left to rescue the second piece. Look for squares where your piece gives check and simultaneously attacks an undefended queen or rook. It is the most reliable fork of all, because your opponent literally has no choice.
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 #854.
SP-854 · RampartGuard — A b- or g-file king and two knights on inner files (b–g).
The king starts on b1, the rooks on a1 and e1, the queen on h1.
From b1 the king makes the longest journey Chess960 allows when castling short: five squares to g1.
The bishops stand on c1 and f1; their long diagonals reach h6 and a6 once the d- and e-pawns step aside.
The pawn on c2 is defended by the king alone — the same soft spot f2 is in the classical setup.
The setup belongs to the RampartGuard family; read right to left it becomes position 102.
The engine's main line opens with e4, putting a pawn straight into the centre.
Morozov Balance Index: 51 of 100 — class C — noticeable edge. Engine evaluation of the starting position: +26 centipawns for White (depth 45, 400 000 000 nodes).
Explore position #854Provenance
Mined from the project's engine self-play games.
Pack 015 · SP-854
Similar puzzles
In your browser or in the Android app. Nothing to install · Free, no ads