Attack on the uncastled king: king to h3 (g2)
c9-21399naming 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 1250 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 g2, rook f1, bishop b2 c6, knight a1, pawn a2 h2 d3 b4 e4 d6.
Black: king e8, rook d7 f8, knight e3 c7, pawn a7 h7.
11 white and 7 black pieces are on the board; the puzzle position arises after move 26.
The position in numbers
White are ahead by 2 points of material (20 against 18; pawn = 1, knight and bishop = 3, rook = 5, queen = 9) — the tactic has to convert or outweigh that.
The white king stands on g2, the black king on e8.
It is White to move on move 26, with 4 legal replies to weigh — only the line that keeps the advantage solves the puzzle. White are in check right now, so every reply must answer the check.
White keeps 6 pawns, Black 2. Files fully open (no pawns of either colour): c, f, g — natural highways for the rooks and queen.
White hold the bishop pair, an edge in open lines. The White king has 4 empty squares to step to right now — the fewer they are, the closer a mating net.
Solution & explanation
Main line
26. Kh3 Nxf1 27. dxc7 Ke7 28. Bxd7
Why it works
- Great move! king to h3 keeps the pressure (+2.2).
- Spot on — pawn to c7 (+2.4).
- Stunning! bishop to d7 gives up material but you stand better (+2.3).
- You win a piece — the rook.
- If instead Nxf1, then dxc7 and you stay on top.
Move by move
- 26. Kh3 — king to h3
- Nxf1 — knight to f1 (capture)
- 27. dxc7 — pawn to c7 (capture)
- Ke7 — king to e7
- 28. Bxd7 — bishop to d7 (capture)
Types in this puzzle
Sacrifice attack
Give up material to unleash a decisive attack.
A sacrificial attack gives up material on purpose to rip the king's shelter open and launch a decisive assault. The sac is sound when you get concrete assets in return: open lines to the king, tempi, pieces ready to pour in. The signs: a poorly sheltered king, your forces aimed at its home, defenders stranded far away. The iron rule is to calculate, not hope — once the material is gone, there is no way back.
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.
Absolute pin
A piece is pinned against its king — it cannot legally move.
An absolute pin freezes a piece on the line between its own king and your long-range attacker: moving it is simply illegal. The pattern is three units on one straight line — your bishop, rook or queen, an enemy piece, and the enemy king behind it. A pinned piece neither attacks nor defends anything: treat it as if it were off the board. Pile up on it, ideally with a pawn, because running away is against the rules.
About this position
These pieces come from starting position #373.
SP-373 · ThroneScout — A central king (d or e), but with a knight posted out on the a- or h-file.
The king starts on e1, the rooks on b1 and f1, the queen on h1.
The kingside rook already stands on f1, so castling short moves only the king, from e1 to g1.
The bishops stand on c1 and d1; their long diagonals reach h6 and h5 once the d- and e-pawns step aside.
One second-rank pawn starts with no defender at all: a2.
The setup belongs to the ThroneScout family; read right to left it becomes position 298.
The engine's main line opens with f4.
Morozov Balance Index: 3 of 100 — class D — largest edge. Engine evaluation of the starting position: +51 centipawns for White (depth 42, 400 000 000 nodes).
Explore position #373Provenance
Mined from the project's engine self-play games.
Pack 009 · SP-373
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