I quite liked the idea, graphics and music but i think there were some flaws in the gameplay and enemy readability.
1. A simple one to fix: i think the game would have been much nicer for me if the enemies were red or violet or some color other than yourself. i died multiple times because i thought they were just mass i could attach to myself ^^' Or giving them some other malicious feature for better readability.
2. Another problem I think is that firing many slimes until you are really small seems like the best strategy, which is quite tedious. I think either just being able to throw nearly everything at once instead of only being able to split or somehow making it that shooting yourself multiple times isn't as good as a strategy.
3. I think the background spikes from the top should maybe have a bit less contrast as i thought they would actually damage for the first half of playing.
4 Overall the game is a little slow. I think removing or lessening the slowdown on the throwing ability would help there. That's also the reason why it is really punishing to get set back all the way to the beginning
I hope this wasn't too harsh. The game is still really impressive and nicely done. I enjoyed playing it and it sets a nice atmosphere.