A proud and honorable warrior, Knuckles spent most of his life searching for Sonic the Hedgehog, believing him to be the key to finding the Master Emerald, which he saw as his ancestral birthright. To this end, he would form an alliance with Dr. Ivo Robotnik — one that would later prove to be a scheme for Robotnik to take the Master Emerald for himself. Knuckles befriended Sonic after Eggman betrayed him and joined forces with him and Miles "Tails" Prower to defeat Robotnik. After this, the trio formed a new order to protect the Master Emerald from evil, a new order that more alien anthropomorphic animals will soon be a part of in the future. He would start staying at Tom and Maddie's house. Without a quest to fulfill and without settling into his life on Earth, Knuckles was influenced through the spirit of the Great Chief Pachacamac to train Wade Whipple and guide him in the ways of an Echidna warrior so that he could participate in the Bowling Tournament of Champions. Along the way, Knuckles and Wade forged a genuine friendship in their training while being pursued by Agents Willoughby and Mason and many bounty hunters who attempted to capture them. Thanks to Wade's advices, Knuckles learned about Earth customs and learned to relax before being confronted by The Buyer, who sought to take his power, but the echidna defeated him and accepted Earth as his new home. Months later, Knuckles and his friends were recruited by the Guardian Units of Nations to confront Shadow the Hedgehog. Despite their efforts, they were ultimately defeated and forced into an uneasy alliance with Robotnik, however, he later betrayed them, siding with his grandfather, Gerald Robotnik, and Shadow in their plot to use the Eclipse Cannon to destroy the Earth. Determined to stop them, Knuckles and Tails journeyed to the cannon, where they teamed up with Robotnik to put an end to Gerald's scheme. As Super Sonic and Super Shadow successfully halted the cannon, Knuckles and his friends ensured the planet's survival.