Its not really a puzzle as blacks move is not forced.....what if black plays Rd7??? just letting ya know that a puzzle should be forced moves or best moves possible which still lose.

It's not a forced mate in two, though...

1.Nc6 Ra8 stops the mate.

or 1.Nc6 Qf4+ Kb1 (Rb2 pins the rook, and thus stops the mate) Rd7 stops the mate.