Some of the NPCs will shoot at you, which will kill you if the skull gets hit.
I wanted to expand upon the boost thing a bit more and add a size/score counter, but I ran out of time haha
Ah, yes! I played it again, it took me a while of exploring to find someone finally shooting at me! lol
I hope you keep improving this game after the game jam, I think you can achieve something really cool on this game with more time working on it!