Cool! Thanks for letting us know!

I hope this counts as constructive feedback :) :

1. red/pink on green are horrible to read. Use for example white on #2b425d to match the in-game color
2. "Press space to " lacks "start" at end
3. Giggle as death sound makes no sense.
4. "FreeSoundEffects" should be "FreeSound"
5. Ruin tiles, crystals and some of the sounds require you to give direct credit to the authors of the works, rather than just the websites.
6. The combination of jump and damage-pushback shows that at least one of the two must be broken. I don't know how to fix though.
7. I'd add sounds for attacks (spit, smash) and a success/win sounds (maybe a determined "yeah!" - can't find one on freesound right now though) to give more feedback during fights and a little reward at the end
8. Jumping is too hard/fiddly, especially with the getting knocked back and not being able to move during attack in air. to quickly fix this, I'd add double jump.
9. You ask for feedback but give no way of contacting you
10. No way to restart game after end.

Very nice work! Was this part of a jam/hackathon? Will you participate at the global game jam?