Attack on the uncastled king: knight to h5 (f4·2)
c9-26116naming 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 1200 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 g1, queen g6, rook d1, bishop f1 e5, knight f3 f4, pawn a2 d2 f2 g2 e3.
Black: king g8, queen b7, rook h5 d8, bishop a8 f8, knight g7 e8, pawn c5 d5 f6 a7.
12 white and 12 black pieces are on the board; the puzzle position arises after move 16.
The position in numbers
Black are ahead by 4 points of material (31 against 35; pawn = 1, knight and bishop = 3, rook = 5, queen = 9) — the tactic has to convert or outweigh that.
The white king stands on g1, the black king on g8.
It is White to move on move 16, with 50 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 5 pawns, Black 4. Files fully open (no pawns of either colour): b, h — natural highways for the rooks and queen. Half-open for White: c.
The White king has 0 empty squares to step to right now — the fewer they are, the closer a mating net.
Solution & explanation
Main line
16. Nxh5 Qf7 17. Nxf6+ Nxf6 18. Qxf6 Qxf6 19. Bxf6
Why it works
- Great move! knight to h5 keeps the pressure (+3.7).
- Well found: knight to f6 (+3.5).
- Strong! queen to f6 is the sharp choice (+3.7).
- Great move! bishop to f6 keeps the pressure (+3.7).
- You win a piece — the queen.
- If instead Qf7, then Nxf6+ and you win the rook.
Move by move
- 16. Nxh5 — knight to h5 (capture)
- Qf7 — queen to f7
- 17. Nxf6+ — knight to f6 (capture) with check
- Nxf6 — knight to f6 (capture)
- 18. Qxf6 — queen to f6 (capture)
- Qxf6 — queen to f6 (capture)
- 19. Bxf6 — bishop to f6 (capture)
Types in this puzzle
Winning exchange
A forced series of captures on one square ends in your favour.
A winning exchange is a forced series of captures on one square that leaves you ahead in material. It is pure arithmetic: count the attackers and defenders of the square and note the value of every piece in the queue. Capture in the right order — cheap pieces first, expensive ones later — or a winning trade turns into a losing one. The classic error is stopping the count halfway and missing the opponent's final recapture.
Counter-strike
Don't defend — answer the threat with a bigger one.
The counter-strike: instead of defending against the threat, you answer with a bigger threat of your own. While your opponent grabs a pawn, you deliver mate — the arithmetic favors you. Look for a counter when direct defenses fail: do you have a check, an attack on the queen, a mating threat? The beginner's error is meeting every threat with a reflexive defense without checking the counterattacking resources first.
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 #98.
SP-98 · RampartGuard — A b- or g-file king and two knights on inner files (b–g).
The king starts on g1, the rooks on d1 and h1, the queen on b1.
The king already stands on its castled square, so castling short moves only the rook, from h1 to f1.
A bishop starts in the corner on a1: it has a single diagonal, which the b-pawn unlocks, running out to h8.
The pawn on f2 is defended by the king alone — the classic soft spot of the standard setup.
The setup belongs to the RampartGuard family; read right to left it becomes position 855.
The engine's main line opens with b4.
Morozov Balance Index: 83 of 100 — class A — most balanced. Engine evaluation of the starting position: +16 centipawns for White (depth 44, 400 000 000 nodes).
Explore position #98Provenance
Mined from the project's engine self-play games.
Pack 008 · SP-98
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