Name a Sonic game,you never played before.

Sonic 2006 (probably for the better)

Sonic Lost World (intentionally skipped it over it being yet another entry in Sola Sonica)

Sonic CD (I haven't played most Classic Sonic games, to be honest)

Sonic 3 and Knuckles

Sonic Shuffle

Sonic Colors (DS)

Sonic Generations (Console and PC version)

Both of the Sonic Boom games

Sonic 2006 and sonic 2