Knuckles the Echidna

Knuckles the Echidna is a character from Sonic the Hedgehog series who debuted in Sonic the Hedgehog 3.

In Super Smash Bros. Brawl
Knuckles is mentioned by Sakurai in Sonic The Hedgehog: Angel Island Zone update, referring to his first appearance. Though it is unknown at the moment if he will make any appearance in the game.