Knuckles is a fictional character from the Sonic the Hedgehog video game series created by Sega. He is an anthropomorphic red echidna known for his strength and determination. Knuckles serves as the guardian of the Master Emerald, a powerful gem that maintains the balance of the floating Angel Island. First introduced in Sonic the Hedgehog 3 in 1994, Knuckles is often portrayed as a rival to Sonic but eventually becomes one of his allies. He is characterized by his spiked knuckles, which he uses for digging and climbing, and his goal to protect his home from various threats, including the villain Dr. Robotnik.