Knuckles the Echidna (ナックルズ・ザ・エキドゥナ, Nakkurusu za Ekiduna) is a red anthropomorphic echidna, who is very powerful and a bit short tempered.
His color scheme is scarlet with a white crecent moon on his chest, royal purple eyes and peach skin. Knuckles is the only Sonic character without any visable ears.
He is as strong as Sonic is fast. In addition to his strength, Knuckles can glide, which comes in handy in his search for the Master Emerald pieces.
Knuckles' name is derived from the four knuckles, two on each hand, which are actually sharp spikes.
According to official Sonic Team polls, Knuckles is a very popular character in the series, coming in fourth place after Sonic, Shadow and Tails.
His first game appearance was in Sonic the Hedgehog 3, released on February 2, 1994 for the Sega Mega Drive/Genesis.