Winning blow: queen to b6 (a6·2)
c9-16781naming 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 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.
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 e1, queen a6, rook b1 h1, bishop a1, knight d1 e6, pawn a2 d2 g2 e3 f3 b4 h4.
Black: king g8, queen d8, rook b6 e8, bishop g7 a8, knight f6, pawn d5 e5 h5 g6 c7.
14 white and 12 black pieces are on the board; the puzzle position arises after move 17.
The position in numbers
White are ahead by 2 points of material (35 against 33; pawn = 1, knight and bishop = 3, rook = 5, queen = 9) — the tactic has to convert or outweigh that.
The white king stands on e1, the black king on g8.
It is White to move on move 17, with 48 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 7 pawns, Black 5. No file is fully open, so the heavy pieces have to be pried in. Half-open for White: c.
Black hold the bishop pair, an edge in open lines. The White king has 4 empty squares to step to right now — the fewer they are, the closer a mating net.
Solution & explanation
Main line
17. Qxb6 cxb6 18. Nxd8
Why it works
- Great move! queen to b6 keeps the pressure (+4.3).
- Well found: knight to d8 (+4.2).
- You win a piece — the queen.
- If instead cxb6, then Nxd8 and you win the queen.
Move by move
- 17. Qxb6 — queen to b6 (capture)
- cxb6 — pawn to b6 (capture)
- 18. Nxd8 — knight to d8 (capture)
Types in this puzzle
Relative pin
A piece shields a more valuable one behind it — moving it loses material.
In a relative pin the piece shields not its king but something valuable behind it, usually the queen. Moving is legal but costly, because the piece behind falls. Look for three units on one line: your long-range piece, a cheaper enemy piece, and an expensive one hiding behind. Beware the classic trap — a relatively pinned piece can still move with check or a bigger threat, so verify before you cash in.
About this position
These pieces come from starting position #498.
SP-498 · ThroneGuard — King on a central file (d/e) with both knights on inner files — the classic-type setup.
The king starts on e1, the rooks on b1 and h1, the queen on c1.
Castling ends where it always does: king to g1 and rook to f1 on the short side, king to c1 and rook to d1 on the long one.
A bishop starts in the corner on a1: it has a single diagonal, which the b-pawn unlocks, running out to h8.
One second-rank pawn starts with no defender at all: a2.
The setup belongs to the ThroneGuard family; read right to left it becomes position 551.
The engine's main line opens with b4.
Morozov Balance Index: 91 of 100 — class A — most balanced. Engine evaluation of the starting position: +13 centipawns for White (depth 49, 400 000 000 nodes).
Explore position #498Provenance
Mined from the project's engine self-play games.
Pack 007 · SP-498
Similar puzzles
In your browser or in the Android app. Nothing to install · Free, no ads