Sonic Boom: Rise of Lyric was not only the worst Sonic game, but could arguably be considered to be one of (if not) the worst game of all time. Like Sonic 06, the game was plagued with a multitude of glitches.
Darkspine Sonic is one of the most forgotten characters in the series. This transformation only appears in Sonic And The Secret Rings during the final boss. While he's the weakest of the super forms, he's still a force to be reckoned with.