Attack on the uncastled king: rook to d4 (d1·14)
c9-26751naming 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.
Uncastled king: the enemy king is stuck in the centre — punish it before it castles.
Winning tactic: there is a move that gains a decisive advantage — find it.
Difficulty 1390 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.
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.
This position hides a concrete tactic that wins material or mates. Start with the most forcing candidate moves — checks, captures and threats — and calculate each to a clear end before choosing; the winning line is usually the one the opponent cannot meet.
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, rook d1 e1, bishop c1 h1, knight b3 e5, pawn a2 b2 f2 h2 c3 g3.
Black: king f8, rook d8 g8, bishop f6 c8, knight a4 c7, pawn g4 d5 c6 a7 b7 h7.
13 white and 13 black pieces are on the board; the puzzle position arises after move 16.
The position in numbers
Material is level — 28 points of pieces on each side (pawn = 1, knight and bishop = 3, rook = 5, queen = 9).
The white king stands on f1, the black king on f8.
It is White to move on move 16, with 38 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): e — natural highways for the rooks and queen. Half-open for White: d.
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
16. Rd4 Nb6 17. Bh6+ Ke8 18. Nxc6+ Kd7 19. Nxd8
Why it works
- Great move! rook to d4 keeps the pressure (+3.6).
- Well found: bishop to h6 (+4.8).
- Precise: knight to c6 is the top choice (+4.8).
- Best move. knight to d8 is exactly what the engine plays (+3.9).
- You win a piece — the rook.
- If instead Nb6, then Bh6+ and you stay on top.
Move by move
- 16. Rd4 — rook to d4
- Nb6 — knight to b6
- 17. Bh6+ — bishop to h6 with check
- Ke8 — king to e8
- 18. Nxc6+ — knight to c6 (capture) with check
- Kd7 — king to d7
- 19. Nxd8 — knight to d8 (capture)
Types in this puzzle
Relative pin
A piece shields a more valuable one behind it — moving it loses material.
In a relative pin the piece shields not its king but something valuable behind it, usually the queen. Moving is legal but costly, because the piece behind falls. Look for three units on one line: your long-range piece, a cheaper enemy piece, and an expensive one hiding behind. Beware the classic trap — a relatively pinned piece can still move with check or a bigger threat, so verify before you cash in.
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.
Discovered check
The moving piece opens a check — and is free to grab anything meanwhile.
With a discovered check the moving piece unmasks a check from the piece standing behind it. While the king deals with the check, the piece that moved grabs whatever it likes, free of charge. Look for your long-range piece on a line with the enemy king, with exactly one of your own pieces in between. The rule: among all the ways to step aside, pick the one that captures or attacks the most expensive loot.
About this position
These pieces come from starting position #55.
SP-55 · BastionScout — A c- or f-file king with at least one knight out on the edge.
The king starts on f1, the rooks on d1 and g1, the queen on e1.
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 h1: it has a single diagonal, which the g-pawn unlocks, running out to a8.
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 898.
The engine's main line opens with d4, putting a pawn straight into the centre.
Morozov Balance Index: 34 of 100 — class C — noticeable edge. Engine evaluation of the starting position: +31 centipawns for White (depth 43, 400 000 000 nodes).
Explore position #55Provenance
Mined from the project's engine self-play games.
Pack 010 · SP-55
Similar puzzles
In your browser or in the Android app. Nothing to install · Free, no ads