Winning blow: bishop to a8 (h1·4)
c9-10563naming 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.
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.
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 d1, rook c5, bishop h1, knight c2, pawn a2 h2 c3.
Black: king b8, rook e6 a8, bishop g8, pawn g4 g6 h6 a7.
7 white and 8 black pieces are on the board; the puzzle position arises after move 26.
The position in numbers
Black are ahead by 3 points of material (14 against 17; pawn = 1, knight and bishop = 3, rook = 5, queen = 9) — the tactic has to convert or outweigh that.
The white king stands on d1, the black king on b8.
It is White to move on move 26, with 31 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 3 pawns, Black 4. Files fully open (no pawns of either colour): b, d, e, f — natural highways for the rooks and queen. Half-open for White: g.
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
26. Bxa8 Kxa8 27. Rc8+ Kb7 28. Rxg8
Why it works
- Brilliant! The bishop on a8 is a sacrifice that works — you are winning (+3.0).
- Well found: rook to c8 (+3.2).
- Strong! rook to g8 is the sharp choice (+3.3).
- You win a piece — the rook.
- If instead Kxa8, then Rc8+ and you stay on top.
Move by move
- 26. Bxa8 — bishop to a8 (capture)
- Kxa8 — king to a8 (capture)
- 27. Rc8+ — rook to c8 with check
- Kb7 — king to b7
- 28. Rxg8 — rook to g8 (capture)
Types in this puzzle
Royal fork
A fork with check: the king must move, and the second piece is lost.
A royal fork is a fork with check — one of the two targets is the king itself. The check must be answered first, so nobody is left to rescue the second piece. Look for squares where your piece gives check and simultaneously attacks an undefended queen or rook. It is the most reliable fork of all, because your opponent literally has no choice.
Endgame tactic
Tactics live in the endgame too — strike while material is scarce.
Tactics do not retire when the queens come off: forks, pins and double attacks live on in the endgame. With so little material left, every tactical loss is almost always decisive. The signs are the usual ones — undefended pieces, king and piece on one line, a pawn about to promote. Even in a "technical" ending, scan for a shot before every move, both yours and your opponent's.
Decoy
A sacrifice lures the king or a piece onto a fatal square.
A decoy is the mirror image of deflection: you sacrifice to drag the king or a piece onto a fatal square. The classic is a queen or rook sac whose capture pulls the king into a knight fork, a discovered check or mate. Find the square where the target will be hit, then find the offer it cannot refuse. Calculate to the very end — a decoy only works when the follow-up is forced.
About this position
These pieces come from starting position #639.
SP-639 · BastionGuard — King shifted to c or f, knights kept clear of the edges — 168 positions in all.
The king starts on c1, the rooks on a1 and e1, the queen on d1.
The king already stands on c1, so castling long moves only the rook, from a1 to d1.
A bishop starts in the corner on h1: it has a single diagonal, which the g-pawn unlocks, running out to a8.
The pawn on b2 is defended by the king alone — the same soft spot f2 is in the classical setup.
The setup belongs to the BastionGuard family; read right to left it becomes position 224.
The engine's main line opens with e4, putting a pawn straight into the centre.
Morozov Balance Index: 37 of 100 — class C — noticeable edge. Engine evaluation of the starting position: +30 centipawns for White (depth 48, 400 000 000 nodes).
Explore position #639Provenance
Mined from the project's engine self-play games.
Pack 006 · SP-639
Similar puzzles
In your browser or in the Android app. Nothing to install · Free, no ads