Knuckles the Echidna is a character from Sega's Sonic the Hedgehog series. He is a red anthropomorphic short-beaked echidna who is Sonic's secondary best friend and former rival. Determined and serious, but sometimes gullible, he fights his enemies using brute force and strength. His role is established as the guardian of the Master Emerald, a large gemstone which controls the series' integral Chaos Emeralds, and is the last living member of his tribe, the Knuckles clan.

Sonic the Hedgehog 3 is a 1994 platform game developed and published by Sega for the Genesis. Like previous Sonic games, players traverse side-scrolling levels while collecting rings and defeating enemies. They control Sonic and Tails, who attempt to retrieve the Chaos Emeralds to stop Doctor Robotnik from relaunching his space station, the Death Egg, after it crash-lands on a mysterious floating island. Sonic 3 introduces Knuckles the Echidna, the island guardian, who lays traps for Sonic and Tails.