Working my way through the endgame compositions in Genrikh Kasparian, 888 Miniature Studies (2010) has put me in the midst of forty studies by A. A. Troitsky (1866-1942).* Many of these feature clever checkmates with knights. Here is an example.
White to move
Kasparian's solution is presumably the one offered by Troitsky. However, playing the position against a computer reveals an alternate solution. In Kasparian's solution, all of White's moves are the only move leading to advantage.
1.Ne3 g5 2.Kf3 g4
Here the computer played 2...h4, leading to 3.g4 Kh2 4.Nf5 Kg1 5.Nxh6 h3 6.Nf5 Kf1 7.Kg3+-.
3.Kf2 h4 4.Ng2 hxg3 5.Kg1
Black to move
Black's king can no longer move, forcing the pawn forward until the king is wholly trapped. Then, the knight delivers checkmate.
5...h5 6.Kh1 h4 7.Nf4#.
*Kasparian employs the spelling Troitski, while most English language texts use Troitsky.