Attack on the uncastled king: pawn to g3 (f2·18)
c9-19289naming 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 920 ShuffleRating — for beginners taking their first steps in Chess960 tactics.
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 e1 h1, bishop c1 h7, knight a1, pawn a2 b2 e2 f2 g2 h3 c4.
Black: king f8, queen g3, rook e8 g8, bishop c8, knight e6 h8, pawn b6 a7 d7 e7 f7 g7.
13 white and 13 black pieces are on the board; the puzzle position arises after move 10.
The position in numbers
Black are ahead by 8 points of material (26 against 34; pawn = 1, knight and bishop = 3, rook = 5, queen = 9) — the tactic has to convert or outweigh that.
The white king stands on f1, the black king on f8.
It is White to move on move 10, with 29 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 7 pawns, Black 6. No file is fully open, so the heavy pieces have to be pried in. Half-open for White: d.
White hold the bishop pair, an edge in open lines. The White king has 1 empty squares to step to right now — the fewer they are, the closer a mating net.
Solution & explanation
Main line
10. fxg3 f6 11. Bxg8
Why it works
- Great move! pawn to g3 keeps the pressure (+3.0).
- A brilliant blow: bishop to g8, and you are winning (+3.1).
- You win a piece — the queen.
- If instead f6, then Bxg8 and you win the queen.
Move by move
- 10. fxg3 — pawn to g3 (capture)
- f6 — pawn to f6
- 11. Bxg8 — bishop to g8 (capture)
Types in this puzzle
First-rank tactic
Pieces still on their starting rank become targets of a first-rank strike.
The first-rank tactic: enemy pieces that never left their starting rank become targets themselves. Standing shoulder to shoulder, they block each other and are often defended by nobody. Look for a strike along the first or eighth rank — a rook or queen that breaks through harvests the undeveloped pieces. The mistake is treating the back rank as a safe "rear area": in Chess960 it can be the most vulnerable place on the board.
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.
Trapped piece
The attacked piece has no safe square — it is caught.
Trapping a piece means the attacked piece has no safe square left — it simply perishes. Do not chase it around; build a cage instead: cut off the escape squares with pawns and pieces first, and attack last. The typical victim has wandered deep into your camp or is stuck at the edge of the board, where its mobility is tiny. And always check the way home for your own raiders — or the trapped piece will be yours.
About this position
These pieces come from starting position #308.
SP-308 · BastionScout — The king starts one file off-centre, on c or f, and a knight begins in a corner.
The king starts on f1, the rooks on e1 and g1, the queen on d1.
Castling short simply swaps the two pieces: the king on f1 and the rook on g1 trade places.
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: h2.
The setup belongs to the BastionScout family; read right to left it becomes position 366.
The engine's main line opens with O-O, bringing the king out to g1.
Morozov Balance Index: 40 of 100 — class C — noticeable edge. Engine evaluation of the starting position: +29 centipawns for White (depth 46, 400 000 000 nodes).
Explore position #308Provenance
Mined from the project's engine self-play games.
Pack 005 · SP-308
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