Shadow is a brooding, dark, intimidating hedgehog who is apparently The Ultimate Lifeform. He is a black-furred anthropomorphic hedgehog with red eyes, fangs, a patch of white fur on his chest, a black nose, a tan muzzle and small and triangular ears with tan canals. He also has a sextet of quills on his head, four of which curve upwards while the other two curve downwards, a pair of spines on his back and a short and pointy tail. He has red stripes on each of his head quills, around the edges of his eyes and on his arms and legs. For attire, Shadow wears white gloves with black cuffs and red tongues, and Air Shoes which, like his gloves, have black cuffs and red tongues. Shadow also wears Limiter Rings, one on each of his wrists and ankles.

Sonic is a cocky, heroic, undependable hedgehog who can just run at the speed of sound, also has a craving for chili dogs for some reason. He is an anthropomorphic hedgehog with blue fur that covers most of his body, and peach skin on his arms, muzzle, insides of his ears and front torso. He has small, triangular ears on his head, six long quills on the back of his head, two spines protruding from his back, a short tail, and two emerald green eyes. For attire, he wears red shoes with white socks and white gloves with Ruby red markings on the sock-like cuffs.

Tails is a small, genius, inventor fox who usually tags along with his best pal, Sonic. He is an anthropomorphic fox cub with two tails. He possesses mostly amber fur with white countershading around his muzzle with cheek tufts, belly and the tips of his tails. He also has large triangular ears with white canals on top of his head, a small black nose and three locks of hair on his forehead. For attire, he wears cuffed white gloves, white socks and red shoes with white tips.

Knuckles is a strong, hot headed, tough echidna who is the guardian of the master emerald. He is an anthropomorphic echidna with red fur that covers most of his body, a black nose on his peach-skinned muzzle, a white and crescent-shaped patch of fur on his chest and sharp teeth. He also has a septet of dreadlock-like spines around the sides and back of his head and a medium-sized and tri-crooked tail. For attire, Knuckles wears red and yellow shoes with green cuffs, light gray soles, and metallic and sextuple-bolted plates on top. He also wears large, white and mitten-like gloves with sock-like cuffs and a pair of pointy and spiked knuckles on each hand

Amy is a bright, cheerful, strong hedgehog who basically loves Sonic and has a hammer. She is a pink-furred anthropomorphic hedgehog with bright green eyes and peach skin covering her muzzle, inner ears and arms. She has a small black nose, and small triangular ears on top of her head. She has two medium-length eyelashes on each side of her eyes. She also has three spikes for bangs on her head and a short pointy tail. Her head quills point downwards, somewhat resembling a bob cut. For attire, she sports a red sleeveless dress with two white trims and a white petticoat underneath, tall red boots with a white stripe down the center, white cuffs and gray soles with chunky heels, a red hairband, and white wrist-length gloves with gold bracelets.