Attack on the uncastled king: pawn to d4 (d2·2)
c9-20138naming 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 1110 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 b1, queen e1, rook d1 b4, bishop f1 a3, knight e2 g3, pawn c2 d2 g2 h2 b3.
Black: king b8, queen e5, rook a8 d8, bishop c8, knight c6 f7, pawn a5 b5 f5 g5 c7 h7.
13 white and 13 black pieces are on the board; the puzzle position arises after move 19.
The position in numbers
White are ahead by 2 points of material (36 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 b1, the black king on b8.
It is White to move on move 19, with 29 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 5 pawns, Black 6. Files fully open (no pawns of either colour): e — natural highways for the rooks and queen. Half-open for White: a, f.
White 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
19. d4 axb4 20. dxe5
Why it works
- Great move! pawn to d4 keeps the pressure (+4.1).
- Well found: pawn to e5 (+4.1).
- You win a piece — the queen.
- If instead axb4, then dxe5 and you win the queen.
Move by move
- 19. d4 — pawn to d4
- axb4 — pawn to b4 (capture)
- 20. dxe5 — pawn to e5 (capture)
Types in this puzzle
Discovered attack
A piece steps aside and opens a second attack from the piece behind it.
A discovered attack works like a curtain: one piece steps off the line and unveils the long-range piece behind it. The beauty is that the moving piece can create a second threat of its own — two attacks in one move. Look for your stacked pairs: a bishop or rook behind a knight or pawn, aimed through them at something valuable. Send the front piece to the most aggressive square — a discovery without a second threat wastes half its power.
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.
Quiet move
No check, no capture — yet this modest move decides the game.
A quiet move gives no check and takes nothing — yet it decides the game by creating an unstoppable threat or stealing the king's last square. This is the hardest class of moves: the eye hunts for loud blows while a modest shift does the winning. The clue: every forcing try runs into a defense, so seek the move that strengthens the threat or takes squares away. Train yourself to ask: what if I neither capture nor check, but quietly improve?
About this position
These pieces come from starting position #918.
SP-918 · RampartScout — King on the wing (b/g) with a knight on the rim (a/h) — the rarest family.
The king starts on b1, the rooks on a1 and d1, the queen on e1.
From b1 the king makes the longest journey Chess960 allows when castling short: five squares to g1.
The bishops stand on c1 and f1; their long diagonals reach h6 and a6 once the d- and e-pawns step aside.
One second-rank pawn starts with no defender at all: h2.
The setup belongs to the RampartScout family; read right to left it becomes position 38.
The engine's main line opens with f4.
Morozov Balance Index: 86 of 100 — class A — most balanced. Engine evaluation of the starting position: +15 centipawns for White (depth 48, 400 000 000 nodes).
Explore position #918Provenance
Mined from the project's engine self-play games.
Pack 007 · SP-918
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