Black to play

Once again, going through the main motifs/candidate moves + a bit of calculation are necessary here ( no opening book or ending manual is needed; Chess engines will find the right move instantly)...
Chess Tactics and Combinations. Features Grandmaster opening and middlegame. Hints, Solutions and Analysis provided. Carlsen, Anand, Kasparov,Firouzja,Caruana games. Keep your game sharp ! --------------- (all material copyrighted)
Solution: See Below
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1..Nc2! 2 Nc5 Na3+ 3 Ka2 Qc5 4 Na4 Nc2!
( Threatening Rb2 #) 5 Kb1 Qa3! 0-1
( Idea 6 Qc2 Rfc8! wins)