Attack on the uncastled king: bishop to g3 (h4)
c9-08158naming 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.
Uncastled king: the enemy king is stuck in the centre — punish it before it castles.
Winning tactic: there is a move that gains a decisive advantage — find it.
Difficulty 780 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.
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.
This position hides a concrete tactic that wins material or mates. Start with the most forcing candidate moves — checks, captures and threats — and calculate each to a clear end before choosing; the winning line is usually the one the opponent cannot meet.
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 c1, rook a1 f1, bishop b1 h4, knight f3, pawn a2 b2 d2 g2 e3 h3 c4.
Black: king d8, queen g3, rook a8 f8, bishop c6 b8, knight e4 h8, pawn c5 d6 a7 b7 e7 f7 g7 h7.
14 white and 16 black pieces are on the board; the puzzle position arises after move 10.
The position in numbers
Black are ahead by 4 points of material (35 against 39; 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 d8.
It is White to move on move 10, with 27 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 7 pawns, Black 8. No file is fully open, so the heavy pieces have to be pried in. Half-open for White: f.
The White king has 2 empty squares to step to right now — the fewer they are, the closer a mating net.
Solution & explanation
Main line
10. Bxg3 Nxg3 11. Re1 O-O 12. d4
Why it works
- Brilliant! The bishop on g3 is a sacrifice that works — you stand better (+2.0).
- rook to e1 develops smoothly.
- A natural move: pawn to d4.
- You win a piece — the queen.
- If instead Nxg3, then Re1 and you win the queen.
Move by move
- 10. Bxg3 — bishop to g3 (capture)
Types in this puzzle
Corner bishop
A bishop born in the corner rakes the longest diagonal.
The corner bishop: in Chess960 a bishop often starts on a1 or h1, staring down the longest diagonal from birth. One pawn move and it fires across the entire board, hitting a rook or king in the far corner. In every starting position inspect the long diagonals: whose bishop sits in the corner, what blocks its path, which pawn move opens the line. The mistake is noticing the enemy corner bishop only after it has collected its loot.
Winning blow
Find the strike that wins material by force.
A winning blow is a forced material gain that does not fit a single textbook motif. The general tactical recipe applies: spot loose pieces, an awkwardly placed king, overloaded lines. Go through the forcing moves in order of violence — checks, captures, threats — because most combinations start with one of them. Do not judge by feel: calculate the concrete line until the outcome is beyond doubt.
Uncastled king
The king lingered in the middle — punish the delay.
Punishing the uncastled king: your opponent delayed castling, and now his king is stuck on its starting square under fire. In Chess960 this is deadlier than in classical chess — the king may start in the center or near the edge, and the familiar defensive setups simply do not apply. The signs: the victim still holds castling rights, and the files toward his king are half-open. Open lines before the king manages to hide.
About this position
These pieces come from starting position #888.
SP-888 · ThroneScout — King on a central file (d/e) with a knight starting on the rim (a/h).
The king starts on d1, the rooks on a1 and f1, the queen on c1.
The kingside rook already stands on f1, so castling short moves only the king, from d1 to g1.
The bishops stand on b1 and e1; their long diagonals reach h7 and a5 once the c- and d-pawns step aside.
The second rank carries 2 pawns with no defender at all: g2, h2.
The setup belongs to the ThroneScout family; read right to left it becomes position 77.
The engine's main line opens with c4.
Morozov Balance Index: 47 of 100 — class C — noticeable edge. Engine evaluation of the starting position: +27 centipawns for White (depth 49, 400 000 000 nodes).
Explore position #888Provenance
Mined from the project's engine self-play games.
Verified by Stockfish at depth 20+.
Solution forcedness confirmed (verified).
Pack 003 · SP-888
Similar puzzles
In your browser or in the Android app. Nothing to install · Free, no ads