Chess Strategy

Some months after the Exercise I and Exercise II, it was about time for new challenge, and I picked one example from the absolutely fantastic “John Nunn’s Chess Puzzle Book”. What I liked was the pattern of identifying opponent’s potential and then imposing problems which he cannot solve. Give yourself at least 15 minutes on the board.

White’s king is rather exposed, but it is hard for Black to make progress because of the potential perpetual check on f6 and d8. How should Black continue?

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