Attack on the uncastled king: pawn to g5 (h4·27)
c9-05859naming 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 1060 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 e1, queen a1, rook d1 h1, bishop c1, knight e3 f3, pawn a2 d2 e2 f2 g2 b4 h4 c5.
Black: king e8, queen a8, rook d8 h8, bishop b8 c8, knight g5 f6, pawn b5 c6 d6 g6 a7 e7 g7 h7.
15 white and 16 black pieces are on the board; the puzzle position arises after move 8.
The position in numbers
Black are ahead by 3 points of material (36 against 39; 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 e8.
It is White to move on move 8, with 34 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 8 pawns, Black 8. No file is fully open, so the heavy pieces have to be pried in.
Black hold the bishop pair, an edge in open lines. The White king has 2 empty squares to step to right now — the fewer they are, the closer a mating net.
Solution & explanation
Main line
8. hxg5 a5 9. cxd6 Bxd6 10. gxf6
Why it works
- Great move! pawn to g5 keeps the pressure (+3.1).
- Spot on — pawn to d6 (+3.3).
- Precise: pawn to f6 is the top choice (+3.2).
- You win a piece — the knight.
- If instead a5, then cxd6 and you win the knight.
Move by move
- 8. hxg5 — pawn to g5 (capture)
- a5 — pawn to a5
- 9. cxd6 — pawn to d6 (capture)
- Bxd6 — bishop to d6 (capture)
- 10. gxf6 — pawn to f6 (capture)
Types in this puzzle
Overload
One defender guards two things — it cannot do both jobs.
Overloading exploits a defender with two jobs at once — guarding a piece and covering a mating square, for instance. It cannot do both: your first strike forces it to handle one duty and abandon the other. Find the overworked piece by asking what happens to each of its charges if it gets distracted. Then hit one target and collect the other — an overloaded defender only pretends to defend.
Only move
Everything else loses — find the only move that holds.
An only move is a position where everything loses except one single continuation. You cannot play "by hand" here: run through fundamentally different defenses — run away, block, trade, counterattack — and discard the ones that fail. The hallmark of these puzzles is that the obvious moves lose quickly while the solution often looks strange. First understand exactly what the threat is — then the one saving move reveals itself.
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 #676.
SP-676 · ThroneGuard — A centre-file king with no knight on the edge; a position and its mirror twin always share this family.
The king starts on e1, the rooks on d1 and h1, the queen on a1.
The queenside rook already stands on d1, so castling long moves only the king, from e1 to c1.
The bishops stand on b1 and c1; their long diagonals reach h7 and h6 once the c- and d-pawns step aside.
One second-rank pawn starts with no defender at all: g2.
The setup belongs to the ThroneGuard family; read right to left it becomes position 478.
The engine's main line opens with b3.
Morozov Balance Index: 13 of 100 — class D — largest edge. Engine evaluation of the starting position: +41 centipawns for White (depth 47, 400 000 000 nodes).
Explore position #676Provenance
Mined from the project's engine self-play games.
Verified by Stockfish at depth 20+.
Solution forcedness confirmed (verified).
Pack 006 · SP-676
Similar puzzles
In your browser or in the Android app. Nothing to install · Free, no ads