Knuckles the Echidna is the sole remaining Mobian Echidna and the last in a line of Guardians of Angel Island. From the age of three, Knuckles was trained by his father Locke to assume the mantle of Guardian by the age of ten. Within the last few years, Knuckles has discovered that he is not the last of his kind, and that threats from all over Mobius are threatening his home. While originally operating alone, Knuckles has developed friends and teammates-formed into a group known as the Chaotix, which he leads-over time to assist him with his role of protecting the Floating Island. He has also taken it upon himself to assist those on the surface of Mobius in fighting the forces of Dr. Eggman, most prominently the Knothole Freedom Fighters under Sonic. Knuckles is the last Guardian protecting Angel Island, all other members of the Brotherhood of Guardians having perished or otherwise left incapable of carrying out their duties. He also considers himself responsible for all the Echidna people on Mobius.

Has a cannon voice. For reference, check here:

https://www.youtube.com/watch?v=l6xJELAb1gQ