Mate in 3: queen to d4 (a1)
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The tactical motive
Chess960 twist: use the unusual starting setup of the pieces.
Mate in 3: a forced sequence that ends in checkmate.
Difficulty 1630 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.
In a mate in three every move must be forcing; the defender should never get a free tempo. Find the check or threat that herds the king, calculate the single defence to each, and confirm the net closes on the third move.
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 d2, queen a1, rook b1, bishop g1 h1, pawn h2 d3 f3 b4 g4 b5 d6 c7.
Black: king b6, queen a8, rook e8, bishop f5 g7, knight d4, pawn e4 g5 h5 f6 d7.
13 white and 11 black pieces are on the board; the puzzle position arises after move 22.
The position in numbers
Material is level — 28 points of pieces on each side (pawn = 1, knight and bishop = 3, rook = 5, queen = 9).
The white king stands on d2, the black king on b6.
It is White to move on move 22, with 36 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 8 pawns, Black 5. Files fully open (no pawns of either colour): a — natural highways for the rooks and queen. Half-open for White: e.
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
22. Qxd4+ Kxb5 23. Qc4+ Ka4 24. Ra1#
Why it works
- Great move! queen to d4 keeps the pressure (#2).
- Spot on — queen to c4 (#1).
- Precise: rook to a1 is the top choice (#).
- The line ends in a forced mate in 3.
- If instead Kxb5, then Qc4+ and you stay on top.
Move by move
- 22. Qxd4+ — queen to d4 (capture) with check
- Kxb5 — king to b5 (capture)
- 23. Qc4+ — queen to c4 with check
- Ka4 — king to a4
- 24. Ra1# — rook to a1 and it is checkmate
Types in this puzzle
Mate in 3
A forced checkmate in three moves.
Mate in three is a forced staircase: each of your moves narrows the opponent's choices, and the third one ends the game. Look for the start among checks and sacrifices — quiet first moves are rare in mating problems, but deliciously sneaky. Keep the tree in your head: every defense gets its own branch. Do not stop calculating after move two — see the final mating picture with your own eyes.
Win the pinned piece
The pinned piece cannot run — attack it again and win it.
A pinned piece cannot flee, which means you can win it outright by attacking it one more time. Count attackers against defenders: if you outnumber them, the piece is yours. The best extra attacker is a pawn, since it costs less than anything it might capture. Do not rush the capture — build up the pressure first, then harvest.
Battery
Two pieces stacked on one line — the front one strikes with double force.
A battery stacks two long-range pieces on one line — a queen behind a bishop on a diagonal, or doubled rooks on a file. The front piece strikes with double force: capture it, and the piece behind recaptures with even more pressure. The battery is ready when both pieces already stare at one point and only the front strike is missing. Build batteries in advance on lines leading to the king — the doubling itself often breeds the combination.
About this position
These pieces come from starting position #591.
SP-591 · ThroneGuard — Both knights start on inner files (b–g) while the king sits centrally on d or e — one of 204 positions filed here.
The king starts on d1, the rooks on b1 and e1, the queen on a1.
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 h1: it has a single diagonal, which the g-pawn unlocks, running out to a8.
The pawn on c2 is defended by the king alone — the same soft spot f2 is in the classical setup.
The setup belongs to the ThroneGuard family; read right to left it becomes position 272.
The engine's main line opens with b4.
Morozov Balance Index: 2 of 100 — class D — largest edge. Engine evaluation of the starting position: +54 centipawns for White (depth 41, 400 000 000 nodes).
Explore position #591Provenance
Mined from the project's engine self-play games.
Pack 012 · SP-591
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