Board Thread:General Discussion/@comment-15024974-20140708164905/@comment-15024974-20140708165937

These games are all certainly canon

Sonic 1

Sonic CD

Sonic 2

Sonic 3 and Knuckles

Sonic 4

Sonic Adventure

Sonic Adventure 2

Sonic Heroes

Sonic 06 (This game can be ignored due to it's events being erased from time)

Sonic Unleashed

Sonic Colors

Sonic Generations