This is a really interesting game! I love the concept of becoming the different colours to defeat them, and it is well implemented. Combining that with the player's health was a good choice too imo. I also enjoyed using the player to interact with the menu buttons.
I struggled with the sprint mechanic as it didn't seem to do much, not sure if I was using it correctly. I think it would have been interesting to have more ways to evade and single out enemies too as I found it tricky to defeat them when the other colours caught up with me.
Either way, a great idea and I had a fun time with this!