Chess960 tactic on b6 (d4·2)
c9-12316naming 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.
Mate: a forcing sequence that ends the game — the king has no escape.
Mate in 4: a forced checkmate in four moves — every reply is covered.
Difficulty 2350 ShuffleRating — expert level — few solve it at first try.
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 is a forced mating attack. Start from the enemy king: which of its squares are already covered, and which move takes away the rest while keeping the king in check? Forcing moves — checks and captures — are what turn an attack into mate.
A mate in four is a longer forced net: each of your moves is a check or an irresistible threat, and the king is driven step by step to a square where it is finally trapped. Verify that the defender has exactly one reply at every branch.
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 d1, queen d4, rook b1, bishop h3, knight d7, pawn c2 f2 f3 f6.
Black: king b7, queen h2, bishop f8, pawn a3 b5 c6 g6 f7 h7.
9 white and 9 black pieces are on the board; the puzzle position arises after move 22.
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 d1, the black king on b7.
It is White to move on move 22, with 42 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 4 pawns, Black 6. Files fully open (no pawns of either colour): d, e — natural highways for the rooks and queen. Half-open for White: a, b, g, h.
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
22. Qb6+ Kc8 23. Nc5+ Qxh3 24. Qxc6+ Kd8 25. Nb7#
Why it works
- Best move. queen to b6 is exactly what the engine plays (#3).
- Spot on — knight to c5 (#2).
- Precise: queen to c6 is the top choice (#1).
- Best move. knight to b7 is exactly what the engine plays (#).
- The line ends in a forced mate in 4.
- If instead Kc8, then Nc5+ and you stay on top.
Move by move
- 22. Qb6+ — queen to b6 with check
- Kc8 — king to c8
- 23. Nc5+ — knight to c5 with check
- Qxh3 — queen to h3 (capture)
- 24. Qxc6+ — queen to c6 (capture) with check
- Kd8 — king to d8
- 25. Nb7# — knight to b7 and it is checkmate
Types in this puzzle
Knight mate
The knight lands the killing blow from its unique angle.
In a knight mate the final blow comes from the knight — the only piece whose check can never be blocked. That makes it lethal against a cramped king: only a king move or capturing the knight itself can help. The sign: the squares around the king are occupied or covered, and there is a hop from which the knight checks while staying untouchable. Bring the knight over early — it is slower than the long-range pieces, but its strike cannot be parried.
Mate in 4+
A long forced mating combination.
Mate in four or longer is a marathon of forcing moves where the grip must never loosen. The tools are the same: checks, double threats and sacrifices that deny the opponent a single free tempo. Do not juggle the whole tree at once — walk the main line all the way to mate first, then verify the side branches. If somewhere the defender finds one quiet move that holds, your very first move was wrong.
Counter-strike
Don't defend — answer the threat with a bigger one.
The counter-strike: instead of defending against the threat, you answer with a bigger threat of your own. While your opponent grabs a pawn, you deliver mate — the arithmetic favors you. Look for a counter when direct defenses fail: do you have a check, an attack on the queen, a mating threat? The beginner's error is meeting every threat with a reflexive defense without checking the counterattacking resources first.
About this position
These pieces come from starting position #898.
SP-898 · BastionScout — A knight on the a- or h-file, king on c or f — the mirror twin lands here as well.
The king starts on c1, the rooks on b1 and e1, the queen on d1.
The king already stands on c1, so castling long moves only the rook, from b1 to d1.
A bishop starts in the corner on a1: it has a single diagonal, which the b-pawn unlocks, running out to h8.
The second rank carries 2 pawns with no defender at all: a2, h2.
The setup belongs to the BastionScout family; read right to left it becomes position 55.
The engine's main line opens with f4.
Morozov Balance Index: 51 of 100 — class C — noticeable edge. Engine evaluation of the starting position: +26 centipawns for White (depth 45, 400 000 000 nodes).
Explore position #898Provenance
Mined from the project's engine self-play games.
Pack 015 · SP-898
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