Solution
39. a6 f3 40. ♞xf3 ♝b8 41. a7 ♝xa7 42. ♜xa7
The position
This expert puzzle (rating 2241) asks White to move to find the winning idea. It features these themes: Tactics.
It is White to move. Look for the tactic hiding in the position — Tactics. Drag a piece on the board to play your move; the puzzle will tell you if you found the best continuation.
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