The pawn becoming a knight was unnecessary. If opponent had their pawn to queen, it still isn't stalemate. It was unnecessary to have 3 knights imo.
chess puzzle
(you undoubtly know there is an original which I can't find right now with a similar diagram).
It's not that elegant to start in check. And unnecessary. This version is the same as yours with a white and black move inserted before your sequence:
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That's a great study, but the presentation is not so great.
(1) Source is A. Herbstman & L. Kubbel, Troitzky Tourney 1937, 1st Prize.
(2) Don't modify a study position created by experts, who knew what they were doing. The correct original position is shown by Arisktotle who managed to deduce it.
(3) The study finishes with a remarkable stalemate position involving 3 black knights, and 6...Ke3 – which brings it about – should be given as the main line, not the mundane 6...N2d3 variation.
The study I posted was from a YouTube video by chess.com YouTube channel
I don't know who is responsible for chess.com videos on YouTube but I have never seen any presentation by the chess.com crew which indicates expertise on the subject of chess compositions. Chess.com is basically a game site where the guests and members inject all the composition puzzles, rules and data on the forums and blogs. A notable exception is a course on endgame studies by Oleg Pervakov for which chess.com is to be commended!
Btw, it appears that my diagram in post #4 is indeed the original position of the composition. And there is no reason in the world to skip the first move as in the video!
At 9:31
Ah, I got it! (I think) This is a very famous study and chances are considerable the GMs would recognize the original position. So for fun the show presenter played the first move hoping to confuse their memory systems. I doubt it helped a lot since the original pattern with the 3 knights is still quite recognizable! Possibly he did the same to other puzzles in the video. Didn't check them.
White to move, and draw