Really fun game, looks really nice too. The concept was interesting and you executed it perfectly. Didn't have a lot of issues, imma assume you patched the double jump glitch that other people are talking about because it was fine for me. Other than that, great job!

Graphics are simple but with the help of shadow and some chromatic aberration it looks very nice. Your music is great too. The controls have some issues (perhaps due to lags). I was rarely able to double-jump. I didn't manage too complete level 1 (witch even if I'm a bad platformer player, means it's too hard for a 1st level). Though I think your idea is clever ! Have to plan all to complete the level using mutation specificity, that's great !
Edit: Would make an excelent game to speedrun.

I really enjoyed the game, I think I spent at least an hour trying to beat it :D Loved the simple yet polished-looking aesthetics.  Pretty unique and addictive idea especially since levels are so well designed.
There's just some small problem with the physics of the ball (it doesn't immediately stop when you stop pressing A/D) so jumping on those tiny platforms was in some cases unnecessarily hard. It sometimes happens after teleporting too, got me killed a few times this way.
Also not sure if there's something wrong with ground check or all inputs are not being registered, but double jump was really hard to execute well. It sometimes doesn't work at all which particularly sucks when you have to plan your jumps so accurately in later levels.
Amazing game!

Btw I was wondering what's slowing down the game so much? It's lagging even in windows build, not a lot but still noticeable.

Nice work with the shades, i like 'em