Explanation
Open the explanation (shows the answer)
The answer is h2. With best play to the end: +2 (a win by 2).
Best line: h2 h7 f1 b5 a6 a7 h5 g7 f2 g1
Other moves
| Move | Result | Why |
|---|---|---|
| f1 | -4 (a loss by 4) | Openness: 3 for this move (flips 1), 1 for h2 (flips 3). The opponent's best answer is h2 (then h5 h7 g7). |
| f2 | -4 (a loss by 4) | The opponent's best answer is h2 (then h5 h7 g7). |
| b8 | -4 (a loss by 4) | The opponent's best answer is h2 (then h5 h7 g7). |
| h5 | -6 (a loss by 6) | The opponent's best answer is h2 (then f2 h7 g7). |
| c8 | -12 (a loss by 12) | The opponent's best answer is h7 (then h2 f2 f1). |
| g1 | -20 (a loss by 20) | Openness: 4 for this move (flips 4), 1 for h2 (flips 3). The opponent's best answer is g7 (then h5 h7 b8). |
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.