I saw it in a chess.com article somewhere.
First one to solve this puzzle gets 10 points

@alexandermatos the white king was already in a position where black knights couldnt check white king

@alexandermatos the white king was already in a position where black knights couldnt check white king
The black knights guard any checkmate by white's three knight. After Ka2, Black is forced to move one of his knights and lose the game.

Good idea@redzippy quest
@rg8 check