Mate in 3: rook to b8 (b7·2)
c9-27189naming tag (square·N)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
Position on the board
White: king e2, queen a8, rook b7, knight c5, pawn d2 a3 c3 e3 f4.
Black: king c8, queen b8, rook h1, bishop d6, pawn g3 d5 f5 e6 f7.
9 white and 9 black pieces are on the board; the puzzle position arises after move 32.
Solution & explanation
Main line
32. Rxb8+ Bxb8 33. Qb7+ Kd8 34. Qd7#
Why it works
- Great move! rook to b8 keeps the pressure (#2).
- Spot on — queen to b7 (#1).
- Strong! queen to d7 is the sharp choice (#).
- The line ends in a forced mate in 3.
- If instead Bxb8, then Qb7+ and you win the queen.
Types in this puzzle
Supported queen mate
The queen delivers mate face to face, protected by a friend.
The supported queen mate is the most common pattern of all: the queen lands next to the king and mates because a friendly piece or pawn protects her. The king is helpless — capturing is impossible, and the queen covers every neighboring square herself. Hunt for a protected square beside the enemy king: a knight, bishop or pawn eyeing it turns her invasion into mate. Verify one thing — that the square really is defended, or the king eats her.
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.
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 #248.
SP-248 · ThroneScout — The king starts on d or e while at least one knight begins in a corner.
The king starts on d1, the rooks on c1 and h1, the queen on f1.
Castling long simply swaps the two pieces: the king on d1 and the rook on c1 trade places.
The bishops stand on b1 and e1; their long diagonals reach h7 and a5 once the c- and d-pawns step aside.
One second-rank pawn starts with no defender at all: b2.
The setup belongs to the ThroneScout family; read right to left it becomes position 621.
The engine's main line opens with c4.
Morozov Balance Index: 31 of 100 — class C — noticeable edge. Engine evaluation of the starting position: +32 centipawns for White (depth 46, 400 000 000 nodes).
Explore position #248Provenance
Mined from the project's engine self-play games.
Pack 012 · SP-248
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