I think this was once a daily puzzle.

I'm sure in an actual game I would simply play Rad7+ take the knight on the next move and mate in a couple more, but still a cute puzzle to deliver mate in two.

Numerous moves for Black (four).  The N can go to either 8th ranked square or the King can move to either 8th ranked square defended by the N.

Rhg7 is pretty slick though. I would have gone for the obvious, but inelegant mate in five, taking the N out first.

that is pretty slick! I think a majority of people would have gone for the obvious and passed up the mate in two!

I would have done 1. Rh8+ Ne8

2. Rg8. Kc8

3. Rxe8# 

thats a pretty good one i didnt think of that!

Of course in this position there are a few ways for white to win. Each one of them can show us a little something about how the pieces move. There is no bonus prize for mating quickly in a game, but finding short solutions to puzzles can have good instructive value. The puzzle solution is clever.

Eli's mate in 3 is also a good find. Showing that there is more than one way to skin a cat.

this one is too well known - but I'm sure that when I first saw it [35 years ago] - I must have been delighted... -/

this one aught to be as well-known as philidor's mate. Somehow, novice books do not cover the two-Rs-on-seventh theme thoroughly enough.

Actually, one should exert oneself to make up one's own practice-problems.

really nice position and play, knight being able to block checkmate from both sides, but has to make a move, so has to move knight somewhere else