Attack on the uncastled king: rook to g8 (g5·2)
c9-16090naming 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 c1, queen h4, rook b1 g5, bishop e1 h1, knight c5, pawn c2 h2 a3 d3 e3 b4.
Black: king c8, queen d8, rook d7 g8, bishop f1 f6, knight a8, pawn b5 d5 c6 a7 e7.
13 white and 12 black pieces are on the board; the puzzle position arises after move 18.
The position in numbers
White are ahead by 1 points of material (34 against 33; pawn = 1, knight and bishop = 3, rook = 5, queen = 9) — the tactic has to convert or outweigh that.
The white king stands on c1, the black king on c8.
It is White to move on move 18, with 50 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 6 pawns, Black 5. Files fully open (no pawns of either colour): f, g — natural highways for the rooks and queen.
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
18. Rxg8 Qxg8 19. Qh5 Nb6 20. Nxd7
Why it works
- Great move! rook to g8 keeps the pressure (+3.7).
- queen to h5 develops smoothly.
- Precise: knight to d7 is the top choice (+3.2).
- You win a piece — the rook.
- If instead Qxg8, then Qh5 and you stay on top.
Move by move
- 18. Rxg8 — rook to g8 (capture)
- Qxg8 — queen to g8 (capture)
- 19. Qh5 — queen to h5
- Nb6 — knight to b6
- 20. Nxd7 — knight to d7 (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.
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 #251.
SP-251 · BastionScout — King shifted to c or f, with a knight committed to the corner from move one.
The king starts on c1, the rooks on b1 and g1, the queen on d1.
The king already stands on c1, so castling long moves only the rook, from b1 to d1.
A bishop starts in the corner on h1: it has a single diagonal, which the g-pawn unlocks, running out to a8.
One second-rank pawn starts with no defender at all: a2.
The setup belongs to the BastionScout family; read right to left it becomes position 609.
The engine's main line opens with e4, putting a pawn straight into the centre.
Morozov Balance Index: 6 of 100 — class D — largest edge. Engine evaluation of the starting position: +48 centipawns for White (depth 47, 400 000 000 nodes).
Explore position #251Provenance
Mined from the project's engine self-play games.
Pack 006 · SP-251
Similar puzzles
In your browser or in the Android app. Nothing to install · Free, no ads