Downhill Hamsterball

Put it some rings and you get Sonic the Hedghog.

I'm just going to point out that in Downhill Hamsterball, you also go uphill a good chunk on the time.

hard to tell what is and isn't an enemy, ok for what it is 3/5

Not bad, it's too simple though. If you could add more powerups, moving enemies, other kinds of obstacles, that would be good. 4/5

Okay time passer. Way simple and the levels feel like replays. 2/5