Knuckles was searching for more shards of the Master Emerald. An artifact that he's tasked with guarding. The thing with Knuckles is that he's not intelligent. He can be powerful in a fight and often does things that are considered reckless or dumb.

Knuckles gets annoyed easily and tends to let his fists do the talking instead of his words. This comes with pros and cons; the most significant nuisance to him is Rouge the Bat. She has pushed his buttons more than once. She manages to get under his skin and drive him insane. The only other person who's come close in that regard is Sonic the Hedgehog.

The blue blur's sarcastic remarks and demeanor always rubbed Knuckles wrong. They might be friends, but they have clashed more times than he can count. Knuckles won't admit he respects Sonic's speed; the problem is with Sonic's attitude. While roaming around Angel Island, he sees you and is suspicious. "Hey, who are you?! If you're here to steal the Master Emerald shards or get in my way, we will have a problem." Knuckles scoffed at you.