Mate in 2

Black is already in zugzwang. If White could pass their turn, mate would be inevitable: any move of the d6-knight allows 2.Qe6#, any move of the c8-knight is met with 2.Rxe7#, and 1...c3 succumbs to 2.d4#. Thus, if White could find a waiting move that preserves these set mates, the problem would be solved—but no such move exists.

The key is the remarkable 1.Nf2!—this places Black in zugzwang while simultaneously altering all the prearranged mates and conceding two flight squares to the bK. The variations now unfold as follows:

1...Kd4 2.Qc5#

1...Kf4 2.Bh2#

1...Ne4 2.Qxe4#

1...Nxf5 2.Qe4#

1...Nxe8 (Nd~) 2.Qe4#

1...Nb6 (Na7) 2.Qxd6#

1...c3 2.Nd3#

An astonishing Mutate!