Explanation
Open the explanation (shows the answer)
The answer is h5. With best play to the end: +6 (a win by 6).
Best line: h5 d2 h3 g6 g3 g1 g2 h2 h1 f1
Other moves
| Move | Result | Why |
|---|---|---|
| g3 | -4 (a loss by 4) | Opponent's moves: 5 after this move, 2 after h5. Openness: 4 for this move (flips 1), 1 for h5 (flips 1). The opponent's best answer is g6 (then f3 d2 h3). |
| d2 | -8 (a loss by 8) | Opponent's moves: 4 after this move, 2 after h5. Openness: 4 for this move (flips 3), 1 for h5 (flips 1). The opponent's best answer is g3 (then f3 f1 g1). |
| h3 | -8 (a loss by 8) | Opponent's moves: 4 after this move, 2 after h5. Openness: 3 for this move (flips 1), 1 for h5 (flips 1). The opponent's best answer is g3 (then d2 h5 g6). |
| f3 | -14 (a loss by 14) | Opponent's moves: 5 after this move, 2 after h5. Openness: 3 for this move (flips 4), 1 for h5 (flips 1). The opponent's best answer is d2 (then h5 g3 f1). |
About these puzzles
Each position comes from a real game. The engine solved it to the end (perfect play by both sides) and only positions with a single best move, clearly better than the second-best move, were kept. "Best play wins by N" is the final disc margin when both sides play perfectly.
If you play a different move, you see the final margin your move leads to with perfect play afterwards, and how much it gave up. Results are stored only in this browser.
To be graded during a full game, go to the Reversi dojo.