Super Smash Bros. Maximum/Knuckles the Echidna

Knuckles the Echidna is a red anthromorphic echidna who first appeared in Sonic the Hedgehog 3 and marks his playable debut in Super Smash Bros. Maximum.

Trivia

 * Knuckles, along with Tails and Silver, previously made a cameo in both Super Smash Bros. Brawl and Super Smash Bros. for Wii U and 3DS in the Green Hill stage.