Had some difficulty getting the game to work. For some reason it took a long time to load after I hit start and passed the tutorial room. Visuals and sound were really really good, but I just couldn't figure out what to do. I thought I had a eureka moment, but it didn't seem to do much.
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That's a bit worrying, the game ran smoothly in my testing, but I admittedly didn't check it on anything else but Firefox.
As for the gameplay, you're not missing much, I ran out of time. As is, the game ends when you smash three gems scattered around the world in a single run. You have to dash through enemies and previous iterations of yourself to be able to make it in time. I'll add hints to the description when I get around to updating the itch page so that it's more obvious.
Thanks for checking out my submission!