Winning blow: pawn to b7 (b6·8)
c9-11554naming 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.
Winning tactic: there is a move that gains a decisive advantage — find it.
Difficulty 1250 ShuffleRating — club-player level.
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 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 f2, rook h1, knight a1, pawn d2 e2 g2 h2 f4 b5 b6.
Black: king d8, rook g8, bishop b1, knight a8, pawn d4 f5 d6 g6 a7 h7.
10 white and 10 black pieces are on the board; the puzzle position arises after move 20.
The position in numbers
Black are ahead by 2 points of material (15 against 17; pawn = 1, knight and bishop = 3, rook = 5, queen = 9) — the tactic has to convert or outweigh that.
The white king stands on f2, the black king on d8.
It is White to move on move 20, with 22 legal replies to weigh — only the line that keeps the advantage solves the puzzle.
White keeps 7 pawns, Black 6. Files fully open (no pawns of either colour): c — natural highways for the rooks and queen. Half-open for White: a.
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
20. b7 Kc7 21. bxa8=Q Rxa8 22. Rxb1
Why it works
- Great move! pawn to b7 keeps the pressure (+5.1).
- Spot on — pawn to a8 (+5.4).
- Precise: rook to b1 is the top choice (+5.1).
- You win a piece — the bishop.
- If instead Kc7, then bxa8=Q and you win the knight.
Move by move
- 20. b7 — pawn to b7
- Kc7 — king to c7
- 21. bxa8=Q — pawn to a8 (capture)
- Rxa8 — rook to a8 (capture)
- 22. Rxb1 — rook to b1 (capture)
Types in this puzzle
Promotion
The pawn reaches the last rank and becomes a queen — decisively.
Promotion turns a pawn on the last rank into a queen and rewrites the evaluation on the spot. In tactics the passer rarely walks in for free — usually a sacrifice clears its path. Count the tempi: how many moves does the pawn need, and can the defender stop it in time? And watch the promotion square itself — it must be out of enemy reach or won by force in your combination.
Endgame tactic
Tactics live in the endgame too — strike while material is scarce.
Tactics do not retire when the queens come off: forks, pins and double attacks live on in the endgame. With so little material left, every tactical loss is almost always decisive. The signs are the usual ones — undefended pieces, king and piece on one line, a pawn about to promote. Even in a "technical" ending, scan for a shot before every move, both yours and your opponent's.
Quiet move
No check, no capture — yet this modest move decides the game.
A quiet move gives no check and takes nothing — yet it decides the game by creating an unstoppable threat or stealing the king's last square. This is the hardest class of moves: the eye hunts for loud blows while a modest shift does the winning. The clue: every forcing try runs into a defense, so seek the move that strengthens the threat or takes squares away. Train yourself to ask: what if I neither capture nor check, but quietly improve?
About this position
These pieces come from starting position #245.
SP-245 · ThroneScout — King in the middle of the rank, with a knight already committed to the corner.
The king starts on e1, the rooks on b1 and h1, the queen on f1.
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 c1 and d1; their long diagonals reach h6 and h5 once the d- and e-pawns step aside.
One second-rank pawn starts with no defender at all: a2.
The setup belongs to the ThroneScout family; read right to left it becomes position 618.
The engine's main line opens with f4.
Morozov Balance Index: 24 of 100 — class D — largest edge. Engine evaluation of the starting position: +35 centipawns for White (depth 47, 400 000 000 nodes).
Explore position #245Provenance
Mined from the project's engine self-play games.
Pack 008 · SP-245
Similar puzzles
In your browser or in the Android app. Nothing to install · Free, no ads