Solution
70… ♛f4+ 71. ♚b1 ♛f1 72. ♚a2 g1=♛ 73. ♛xf1 ♛xf1
The position
This expert puzzle (rating 2285) asks Black to move to find the winning idea. It features these themes: Promotion.
It is Black to move. Look for the tactic hiding in the position — Promotion. 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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