Winning blow: bishop to a7 (e3·3)
c9-22437naming 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 1290 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 b1, queen c6, rook a1 h1, bishop e3, knight g3, pawn b2 g2 h2 f4 e5.
Black: king b8, queen f8, rook h8, bishop e7 g8, knight c7, pawn b4 c4 g5 a6 e6 a7 h7.
11 white and 13 black pieces are on the board; the puzzle position arises after move 19.
The position in numbers
Material is level — 30 points of pieces on each side (pawn = 1, knight and bishop = 3, rook = 5, queen = 9).
The white king stands on b1, the black king on b8.
It is White to move on move 19, with 49 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 5 pawns, Black 7. Files fully open (no pawns of either colour): d — natural highways for the rooks and queen. Half-open for White: a, c.
Black hold the bishop pair, an edge in open lines. The White king has 5 empty squares to step to right now — the fewer they are, the closer a mating net.
Solution & explanation
Main line
19. Bxa7+ Kc8 20. Bb6 Qd8 21. Rxa6
Why it works
- Great move! bishop to a7 keeps the pressure (#6).
- Well found: bishop to b6 (#5).
- Precise: rook to a6 is the top choice (#3).
- You win decisive material (+15.0).
- If instead Kc8, then Bb6 and you stay on top.
Move by move
- 19. Bxa7+ — bishop to a7 (capture) with check
- Kc8 — king to c8
- 20. Bb6 — bishop to b6
- Qd8 — queen to d8
- 21. Rxa6 — rook to a6 (capture)
Types in this puzzle
Absolute pin
A piece is pinned against its king — it cannot legally move.
An absolute pin freezes a piece on the line between its own king and your long-range attacker: moving it is simply illegal. The pattern is three units on one straight line — your bishop, rook or queen, an enemy piece, and the enemy king behind it. A pinned piece neither attacks nor defends anything: treat it as if it were off the board. Pile up on it, ideally with a pawn, because running away is against the rules.
About this position
These pieces come from starting position #717.
SP-717 · RampartGuard — King pushed to the b- or g-file, knights off the edges — 144 positions here.
The king starts on b1, the rooks on a1 and h1, the queen on c1.
From b1 the king makes the longest journey Chess960 allows when castling short: five squares to g1.
The bishops stand on d1 and g1; their long diagonals reach h5 and a7 once the e- and f-pawns step aside.
Every pawn on the second rank is defended from the very first move.
The setup belongs to the RampartGuard family; read right to left it becomes position 440.
The engine's main line opens with a4.
Morozov Balance Index: 18 of 100 — class D — largest edge. Engine evaluation of the starting position: +38 centipawns for White (depth 45, 400 000 000 nodes).
Explore position #717Provenance
Mined from the project's engine self-play games.
Pack 009 · SP-717
Similar puzzles
In your browser or in the Android app. Nothing to install · Free, no ads