Explanation
Open the explanation (shows the answer)
The answer is f2. With best play to the end: +4 (a win by 4).
Best line: f2 g3 e2 a5 a4 a3 g2 g1 f1 h1
Other moves
| Move | Result | Why |
|---|---|---|
| b1 | -2 (a loss by 2) | The opponent's best answer is e2 (then f2 g3 g2). |
| g2 | -2 (a loss by 2) | g2 is an X-square (diagonal to the corner h1). While the corner is empty it tends to give the corner away. After this move the opponent can play the corner h1. The opponent's best answer is g3 (then f2 f1 e2). |
| e2 | -4 (a loss by 4) | The opponent's best answer is g3 (then a2 a3 a4). |
| g3 | -8 (a loss by 8) | The opponent's best answer is f1 (then b1 a2 a3). |
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.