Chess960 tactic on d6 (d5·2)
c9-11362naming 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 2400 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 e1, queen a6, rook b1 d5, knight h4 a5, pawn a2 h2 b3 f3 f4.
Black: king b8, queen f8, rook d8, knight d6, pawn c5 f5 g6 a7 d7 e7 h7.
11 white and 11 black pieces are on the board; the puzzle position arises after move 23.
The position in numbers
White are ahead by 6 points of material (30 against 24; 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 b8.
It is White to move on move 23, with 38 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 5 pawns, Black 7. No file is fully open, so the heavy pieces have to be pried in. Half-open for White: c, d, e, g.
The White king has 5 empty squares to step to right now — the fewer they are, the closer a mating net.
Solution & explanation
Main line
23. Rxd6 Kc7 24. Qxa7+ Kxd6 25. Qb6+ Kd5 26. Rd1#
Why it works
- Best move. rook to d6 is exactly what the engine plays (#3).
- Spot on — queen to a7 (#2).
- Precise: queen to b6 is the top choice (#1).
- Great move! rook to d1 keeps the pressure (#).
- The line ends in a forced mate in 4.
- If instead Kc7, then Qxa7+ and you win the knight.
Move by move
- 23. Rxd6 — rook to d6 (capture)
- Kc7 — king to c7
- 24. Qxa7+ — queen to a7 (capture) with check
- Kxd6 — king to d6 (capture)
- 25. Qb6+ — queen to b6 with check
- Kd5 — king to d5
- 26. Rd1# — rook to d1 and it is checkmate
Types in this puzzle
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.
Royal fork
A fork with check: the king must move, and the second piece is lost.
A royal fork is a fork with check — one of the two targets is the king itself. The check must be answered first, so nobody is left to rescue the second piece. Look for squares where your piece gives check and simultaneously attacks an undefended queen or rook. It is the most reliable fork of all, because your opponent literally has no choice.
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 #363.
SP-363 · BastionScout — Off-centre king plus a rim knight (a/h): 168 positions carry this shape.
The king starts on c1, the rooks on b1 and d1, the queen on f1.
The king already stands on c1, so castling long moves only the rook, from b1 to d1.
A bishop starts in the corner on h1: it has a single diagonal, which the g-pawn unlocks, running out to a8.
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 305.
The engine's main line opens with f4.
Morozov Balance Index: 75 of 100 — class A — most balanced. Engine evaluation of the starting position: +19 centipawns for White (depth 45, 400 000 000 nodes).
Explore position #363Provenance
Mined from the project's engine self-play games.
Pack 015 · SP-363
Similar puzzles
In your browser or in the Android app. Nothing to install · Free, no ads