Winning blow: rook to b1 (a1·7)
c9-22768naming 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 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.
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 c3, rook a1 c4, pawn f3 e4.
Black: king b5, rook e2, knight f4, pawn h4 f6 g7.
5 white and 6 black pieces are on the board; the puzzle position arises after move 37.
The position in numbers
White are ahead by 1 points of material (12 against 11; pawn = 1, knight and bishop = 3, rook = 5, queen = 9) — the tactic has to convert or outweigh that.
The white king stands on c3, the black king on b5.
It is White to move on move 37, with 24 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 2 pawns, Black 3. Files fully open (no pawns of either colour): a, b, c, d — natural highways for the rooks and queen. Half-open for White: g, h.
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
37. Rb1+ Ka5 38. Rc8 Re3+ 39. Kc4 Rc3+ 40. Kxc3
Why it works
- Great move! rook to b1 keeps the pressure (#5).
- rook to c8 develops smoothly.
- A natural move: king to c4.
- Great move! king to c3 keeps the pressure (#2).
- You win a piece — the rook.
- If instead Ka5, then Rc8 and you stay on top.
Move by move
- 37. Rb1+ — rook to b1 with check
- Ka5 — king to a5
- 38. Rc8 — rook to c8
- Re3+ — rook to e3 with check
- 39. Kc4 — king to c4
- Rc3+ — rook to c3 with check
- 40. Kxc3 — king to c3 (capture)
Types in this puzzle
Winning blow
Find the strike that wins material by force.
A winning blow is a forced material gain that does not fit a single textbook motif. The general tactical recipe applies: spot loose pieces, an awkwardly placed king, overloaded lines. Go through the forcing moves in order of violence — checks, captures, threats — because most combinations start with one of them. Do not judge by feel: calculate the concrete line until the outcome is beyond doubt.
King march
In the endgame the king is a fighting piece — march it in.
The king march: in the endgame the king is a fighting piece, and often it is his journey forward that wins. It is time to march when the queens are off and checks hold no danger — the king attacks pawns, escorts the passer, takes squares away. The telltale sign of the theme is several king moves in a row. Plan the full route in advance using the rule of the square, and do not let the enemy king grab the opposition.
About this position
These pieces come from starting position #701.
SP-701 · BastionGuard — Off-centre king (c/f), no knight on the a- or h-file.
The king starts on c1, the rooks on a1 and h1, the queen on b1.
The king already stands on c1, so castling long moves only the rook, from a1 to d1.
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 BastionGuard family; read right to left it becomes position 456.
The engine's main line opens with e4, putting a pawn straight into the centre.
Morozov Balance Index: 75 of 100 — class B — balanced. Engine evaluation of the starting position: +19 centipawns for White (depth 45, 400 000 000 nodes).
Explore position #701Provenance
Mined from the project's engine self-play games.
Pack 008 · SP-701
Similar puzzles
In your browser or in the Android app. Nothing to install · Free, no ads