Winning blow: queen to a8 (a7·12)
c9-09146naming 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 1870 ShuffleRating — for advanced tacticians.
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 c1, queen a7, rook a1 f1, knight e3 e4, pawn g2 b3 d3 f3 h4 e5.
Black: king c8, knight f7, pawn a2 d5 b7 c7.
12 white and 6 black pieces are on the board; the puzzle position arises after move 26.
The position in numbers
White are ahead by 24 points of material (31 against 7; pawn = 1, knight and bishop = 3, rook = 5, queen = 9) — the tactic has to convert or outweigh that.
The white king stands on c1, the black king on c8.
It is White to move on move 26, with 45 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 6 pawns, Black 4. No file is fully open, so the heavy pieces have to be pried in. Half-open for White: a, c.
The White king has 6 empty squares to step to right now — the fewer they are, the closer a mating net.
Solution & explanation
Main line
26. Qa8+ Kd7 27. Nc5+ Kc6 28. Qxb7+
Why it works
- Great move! queen to a8 keeps the pressure (#4).
- Spot on — knight to c5 (#3).
- Precise: queen to b7 is the top choice (#2).
- You win decisive material (+15.0).
- If instead Kd7, then e6+ and you stay on top.
Move by move
- 26. Qa8+ — queen to a8 with check
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.
About this position
These pieces come from starting position #828.
SP-828 · BastionScout — King off-centre on c or f with a knight starting on the rim (a/h).
The king starts on c1, the rooks on a1 and f1, the queen on e1.
The king already stands on c1, so castling long moves only the rook, from a1 to d1.
The bishops stand on b1 and g1; their long diagonals reach h7 and a7 once the c- and f-pawns step aside.
One second-rank pawn starts with no defender at all: g2.
The setup belongs to the BastionScout family; read right to left it becomes position 140.
The engine's main line opens with e4, putting a pawn straight into the centre.
Morozov Balance Index: 13 of 100 — class D — largest edge. Engine evaluation of the starting position: +41 centipawns for White (depth 47, 400 000 000 nodes).
Explore position #828Provenance
Mined from the project's engine self-play games.
Pack 014 · SP-828
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