Winning blow: queen to g7 (g2·2)
c9-09443naming 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.
A fork made possible by the Chess960 piece placement.
Winning tactic: there is a move that gains a decisive advantage — find it.
Difficulty 1150 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.
A set-up fork needs one preparing move before the fork lands — a check that drives the king onto the forking square, or a capture that lines the targets up. Find the preparation first, then the fork it makes possible.
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 a2, queen g2, rook c1 g1, pawn b2 a3 c4 d5 h6.
Black: king h8, queen e5, rook f8, pawn a4 b5 c5 d6.
9 white and 7 black pieces are on the board; the puzzle position arises after move 40.
The position in numbers
White are ahead by 6 points of material (24 against 18; pawn = 1, knight and bishop = 3, rook = 5, queen = 9) — the tactic has to convert or outweigh that.
The white king stands on a2, the black king on h8.
It is White to move on move 40, with 33 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 5 pawns, Black 4. Files fully open (no pawns of either colour): e, f, g — natural highways for the rooks and queen.
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
40. Qg7+ Qxg7 41. hxg7+
Why it works
- Best move. queen to g7 is exactly what the engine plays (#7).
- Well found: pawn to g7 (#6).
- You win decisive material (+15.0).
- If instead Qxg7, then hxg7+ and you stay on top.
Move by move
- 40. Qg7+ — queen to g7 with check
- Qxg7 — queen to g7 (capture)
- 41. hxg7+ — pawn to g7 (capture) with check
Types in this puzzle
Setup fork
The random setup allows a fork that classical chess never sees.
A setup fork is a double attack that exists only because of the unusual starting squares — in classical chess these targets never stand side by side. Look for pairs of undefended pieces on your opponent's back rank and for squares from which a knight or pawn hits both at once. Such forks usually appear within the first moves, before the pieces disperse. In every new position, note right away which starting pieces are defended by no one.
Check chase
Every move is a check — the king is chased into losing ground.
In a check chase every one of your moves is a check, so the opponent never gets a free second. The king is herded across the board until it loses a piece or walks into a decisive blow. Such lines are the easiest to calculate: each check allows only a handful of replies, so try them all. Make it a habit to start calculating any sharp position with the checks — they are the most forcing moves on the board.
Simplification
Trade the heavy pieces and steer into a won endgame.
Simplification is how you convert an advantage: by trading queens and rooks you extinguish the counterplay and steer the game into a won endgame. The rule is simple — the side with extra material trades pieces but keeps pawns. Look for exchanges once the material is already won and your opponent is still rattling threats. The mistake is avoiding the queen trade and letting him muddy the water forever.
About this position
These pieces come from starting position #407.
SP-407 · BastionGuard — Off-centre king (c/f), no knight on the a- or h-file.
The king starts on f1, the rooks on a1 and g1, the queen on b1.
Castling short simply swaps the two pieces: the king on f1 and the rook on g1 trade places.
A bishop starts in the corner on h1: it has a single diagonal, which the g-pawn unlocks, running out to a8.
One second-rank pawn starts with no defender at all: h2.
The setup belongs to the BastionGuard family; read right to left it becomes position 738.
The engine's main line opens with d4, putting a pawn straight into the centre.
Morozov Balance Index: 83 of 100 — class A — most balanced. Engine evaluation of the starting position: +16 centipawns for White (depth 45, 400 000 000 nodes).
Explore position #407Provenance
Mined from the project's engine self-play games.
Pack 007 · SP-407
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