Name a Sonic Video Game that you never completed.

Sonic Heroes. Played it a bit when I rented it but didn't really like the game enough to buy it, so never completed it.

Sonic Advance 3. Bad luck, always something happens; virus, my brother deletes, etc

Sonic Blast. It was hard to me haha

Sonic Spinball! dang, that game is sick!

EDIT:
Tails Adventure: DANG! I've enjoyed that game! it was fun haha, but... well, I just didn't finish it. But it was a pretty lovely experience :3

Other ones:
Sonic Chronicles: too close... same stuff with Advance 3. Also Sonic Rush Adventure. I don't have the patience lol

Sonic Labyrinth. Too crappy to finish

Sonic and The Secret Rings. It was really boring to me.

i completed all of them .................... it took me more than one year to do it. but when i finished i acted like this times 1000 but as a girl of course ;D

Sonic1,sonic2,sonic3,
The game sonic classic collection

Sonic blast for game gear
Sonic riders
Flicklys (not sure spelled right)

I never Finnish any sonic game. I'm not really a gamer person. So, all! Besides a Sonic car racing game.

Sonic Unleashed.
Simply lost interest in it.