The desperado

The bishop on c5 will not survive the tactics. Instead of retreating, it spends itself with check and forces White’s rook onto the square a knight fork needs.

Lesson

Black to move. Main line: 1... Bxf2+ 2. Rxf2 Ne3 3. Nb3 Nxd1

1...Bxf2+! is a desperado: a threatened piece takes something useful with tempo before it disappears. White must address the check and 2.Rxf2 is the natural reply.

That recapture enables 2...Ne3, attacking the queen on d1 and exploiting the overloaded white pieces. After the knight sidestep, 3...Nxd1 wins the queen.

When a piece is trapped or already lost, do not save it automatically. Checks and forcing captures may let it perform one final job and improve the whole combination.