Hi. This here is an interesting bullet game where white creates fine attack. I was looking at the situation after 15...Rxf2, and i was not able to find what could black do, to avoid solid material loss or mate. Maybe someone can? I have used Maya pieces style, trying to calm Mayas Gods :)
total eclipse
Sort:
16. Bc4+
sorry.
I don't think this qualifies as an endgame.
i think 4-5 moves before end could be called endgame.
Once upon a time I was falling in love,
But now I'm only falling apart,
There's nothing I can do,
A total eclipse of the heart 
goxie,
I think I see the misunderstanding. Techically you can checkmate on move #2, but that does not mean the starting position is an endgame.
From wikipedia: "In chess and chess-like games, the endgame (or end game or ending) is the stage of the game when there are few pieces left on the board."
This game is still solidly in the middlegame.