Attack on the uncastled king: queen to e7 (e3)
c9-04623naming 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.
A piece strikes across the board from its Chess960 starting square.
Mate in 1: find the move after which the enemy king has no escape.
A fork made possible by the Chess960 piece placement.
Uncastled king: the enemy king is stuck in the centre — punish it before it castles.
Difficulty 850 ShuffleRating — for beginners taking their first steps in Chess960 tactics.
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.
From some Chess960 setups a bishop or queen rakes a long diagonal straight from move one. Trace those long-range lines into the enemy camp: a single opened file or diagonal can create an immediate pin, skewer or mating threat.
A mate in one hides among forcing checks. Run through every check you can give: does it cover all the king's escape squares, is the checking piece safe or supported, and can nothing block or capture it? If yes, that is the mate.
A set-up fork needs one preparing move before the fork lands — a check that drives the king onto the forking square, or a capture that lines the targets up. Find the preparation first, then the fork it makes possible.
An uncastled king in the centre is a standing target. Look for ways to open the central files and diagonals against it with checks and threats before it can shelter — every tempo the king spends in the middle is a chance for a combination.
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 f1, queen e3, rook c1 h1, bishop b4 f5, knight d1 b3, pawn a2 b2 e2 g2 h2 f3 c4 d5.
Black: king f8, queen g8, rook c8 h8, bishop c7 f7, knight f4 a8, pawn h4 c6 f6 a7 b7 d7 e7 g7.
16 white and 16 black pieces are on the board; the puzzle position arises after move 9.
The position in numbers
Material is level — 39 points of pieces on each side (pawn = 1, knight and bishop = 3, rook = 5, queen = 9).
The white king stands on f1, the black king on f8.
It is White to move on move 9, with 56 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 8 pawns, Black 8. No file is fully open, so the heavy pieces have to be pried in.
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
9. Qxe7#
Why it works
- Great move! queen to e7 keeps the pressure (#).
- The line ends in a forced mate in 1.
Move by move
- 9. Qxe7# — queen to e7 (capture) and it is checkmate
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.
Long-range opener
From its unusual home square a long-range piece strikes across the board.
The long-range opener: a bishop, rook or queen strikes across the whole board straight from its starting area. In Chess960 the long-range pieces sit on unfamiliar squares, and a single pawn move can uncover a shot deep into the enemy camp. In the opening, trace with your eyes the diagonals and files of every long-range piece — yours and theirs. The mistake is pushing a pawn without checking whose line you have just opened.
Mate in 1
Checkmate in a single move — find it.
Mate in one: the combination is over, only the final precise shot remains. The method is simple — list every check you have and test the three escapes against each: king moves, blocks, and capturing the checker. If none of them works, it is mate. The classic blunder is falling in love with the first check you see and missing the one escape hatch.
About this position
These pieces come from starting position #168.
SP-168 · BastionScout — King off-centre on c or f with a knight starting on the rim (a/h).
The king starts on f1, the rooks on c1 and h1, the queen on g1.
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.
The bishops stand on b1 and e1; their long diagonals reach h7 and a5 once the c- and d-pawns step aside.
The pawn on e2 is defended by the king alone — the same soft spot f2 is in the classical setup.
The setup belongs to the BastionScout family; read right to left it becomes position 797.
The engine's main line opens with c4.
Morozov Balance Index: 97 of 100 — class A — most balanced. Engine evaluation of the starting position: +7 centipawns for White (depth 45, 400 000 000 nodes).
Explore position #168Provenance
Mined from the project's engine self-play games.
Verified by Stockfish at depth 20+.
Solution forcedness confirmed (verified).
Pack 004 · SP-168
Similar puzzles
In your browser or in the Android app. Nothing to install · Free, no ads