Really well made game! I thought It's gonna be a action game of some sort!
But I can't imagine how you didn't come back to the first level after the end of it... the theme was loop.
I haven't watched the playthrough, but I think I finished some levels in a not so normal way (with getting weird angles and trying to hit some guy with the help of the fan with lots of error and trial)
Killing the boss with one hit was a gigachad move, however I think it would be better if it had stages of some sort (level changes after you hit it each time)
Also giving the boss a way to fight us back would've been cool (and time-taking of course)
It was also really optimized, my low-end laptop could run it without much lag (the web version)!
Good job! And good luck! All these were suggestions, don't take them serious!