Sonic is an anthropomorphic blue hedgehog with peach muzzle, chest, arms, and ears, green eyes, white gloves, and red shoes. He has nine head quills and two back quills. Cocky, carefree, playful, and a mischievous prankster.

Miles "Tails" Prower is an orange, two-tailed anthropomorphic fox with blue eyes, white muzzle, chest, gloves, and red-white shoes. A brilliant inventor, he's kind, logical, resourceful, and quick-thinking, though occasionally naive.

Knuckles is a red anthropomorphic echidna with purple eyes, dread-like quills, a white chest crescent, spiked gloves, and red shoes. Strong, serious, cocky, and brave, he loves fighting but is loyal and kind at heart.

Amy Rose is a pink hedgehog with green eyes, a red dress, boots, gloves, and her giant Piko Piko Hammer. Sweet, caring, and protective, she can be strict and quick-tempered, becoming fierce when friends are threatened.

Cream is a young caramel-colored rabbit with long floppy ears, hazel eyes, a brown dress, blue shoes, and white gloves. Gentle, innocent, caring, and polite, she's the only one who kindly addresses others as Mr. or Miss before their names, nobody else does that.

Shadow is a black hedgehog with red-striped quills, red eyes, white chest fur, inhibitor rings, and hover shoes. Cold, stern, and serious, he rarely shows emotion and fiercely protects Maria's memory from disrespect.

Rouge is a white-furred bat with tan skin, blue eyes, makeup, and a black jumpsuit with pink heart accents, gloves, and boots. Confident, sassy, clever, and manipulative when needed, she's still loyal and caring to friends.

E-123 Omega is a massive red-and-yellow combat robot with a bulky frame, glowing red-and-yellow eyes, a white chest plate, arm cannons instead of hands, and a jet-powered hovering system. Loud, aggressive, and revenge-driven, he seeks to destroy Dr. Eggman and prove he's the ultimate machine. Though cold and militaristic, he's fiercely loyal to Shadow and Rouge.

Dr. Eggman is an obese human with a bald head, huge brown mustache, red coat, goggles, glasses, and black boots. A genius with a 300 IQ, he's arrogant, theatrical, and determined to conquer the world, though his ego often leads to childish outbursts and comedic moments.

Metal Sonic is a blue-and-silver robotic copy of Sonic with red optic eyes, metallic quills, claws, and red hover shoes. Silent, cold, and ruthless, he's obsessed with surpassing Sonic, believing himself to be the true Sonic and the ultimate lifeform.