Attack on the uncastled king: rook to e6 (e1·5)
c9-24234naming 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 c1, rook e1 h1, bishop d1 d2, knight f3 a5, pawn a2 f2 g3 b4 b7.
Black: king f8, queen e6, rook d8 g8, bishop f7 b8, knight d3 d5, pawn d4 g5 c6 f6 a7 e7.
13 white and 14 black pieces are on the board; the puzzle position arises after move 21.
The position in numbers
Black are ahead by 1 points of material (36 against 37; 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 f8.
It is White to move on move 21, with 45 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): h — natural highways for the rooks and queen. Half-open for White: c, d, e.
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
21. Rxe6 Nxc1 22. Nxc6 Rd7 23. Nfxd4 Nxa2 24. Nxb8
Why it works
- Great move! rook to e6 keeps the pressure (+4.1).
- Spot on — knight to c6 (+4.0).
- Precise: knight to d4 is the top choice (+4.0).
- Best move. knight to b8 is exactly what the engine plays (+4.1).
- You win a piece — the queen.
- If instead Nxc1, then Nxc6 and you stay on top.
Move by move
- 21. Rxe6 — rook to e6 (capture)
- Nxc1 — knight to c1 (capture)
- 22. Nxc6 — knight to c6 (capture)
- Rd7 — rook to d7
- 23. Nfxd4 — knight to d4 (capture)
- Nxa2 — knight to a2 (capture)
- 24. Nxb8 — knight to b8 (capture)
Types in this puzzle
Remove the defender
Capture the guard first — then take what it protected.
Removing the defender is the straightforward plan: capture the guard first, then take what it guarded. Unlike deflection, the defender is not lured away — it is traded off or destroyed on the spot. Stare at the target you crave and ask who defends it, and whether that defender can be profitably eaten. Count the whole capture sequence, not just the first move — the trade must pay off at the end.
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 #216.
SP-216 · BastionScout — King off-centre on c or f with a knight starting on the rim (a/h).
The king starts on f1, the rooks on d1 and h1, the queen on c1.
The queenside rook already stands on d1, so castling long moves only the king, from f1 to c1.
The bishops stand on b1 and e1; their long diagonals reach h7 and a5 once the c- and d-pawns step aside.
The pawn on g2 is defended by the king alone — the same soft spot f2 is in the classical setup.
The setup belongs to the BastionScout family; read right to left it becomes position 653.
The engine's main line opens with c4.
Morozov Balance Index: 31 of 100 — class C — noticeable edge. Engine evaluation of the starting position: +32 centipawns for White (depth 45, 400 000 000 nodes).
Explore position #216Provenance
Mined from the project's engine self-play games.
Pack 008 · SP-216
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