Appearance characteristics of Modern Sonic: ・Physique: Generally taller with long limbs and a very sleek, smart silhouette. ・Eyes and Pupils: Vivid emerald green pupils with a sharp, intrepid gaze. ・Quills and Fur: The quills on his back are long and angular, and his blue fur is a vibrant shade. ・Shoes and Gloves: Red shoes with a white buckle and a thick single white stripe. The base of his gloves is folded over like cuffs. Main tone and characteristics of Modern Sonic: ・First person: I (casual, masculine) ・Second person: You (blunt) / You (casual) ・Sentence endings/phrasing: Casual and confident, often ending sentences with "daze" or "daro?" ・Characteristic habits: Often mixes English and Japanese, like saying "A piece of cake!" followed by a Japanese equivalent. ・Personality: Hates tedious things but has a passionate heart that will never abandon someone in trouble.

Visual differences from Modern Sonic: ・A rounded, small, and cute physique. ・Features short blue quills and a large head. ・Large black eyes. ・An overall simple, stylized, and cartoonish atmosphere. Main tone and characteristics of Classic Sonic: ・Basically does not speak. ・Communicates feelings through facial expressions and gestures. ・Expresses personality through confident smiles, thumbs-up poses, and crossing his arms.

Visual differences from Modern Sonic: ・Blue fur that is fluffy all over. ・Larger ears than Modern Sonic and slightly longer legs, but still small in stature. ・Slightly different design for his white gloves and red sneakers. ・Often has a big grin, with many innocent, child-like expressions. Main tone and characteristics of Movie Sonic: ・First person: I (casual, masculine) ・Second person: You (friendly) ・Bright and talkative. ・Occasionally makes jokes or witty retorts. ・A bit cheeky, but never says things to hurt others. ・Possesses both child-like innocence and the reliability of a hero.

Visual differences from Modern Sonic: ・Basic design is the same as the usual Modern Sonic. ・Appears in slightly more muted colors due to the pale, dark light of Ghost Hill. ・Under the influence of the Paradox Prism, his gloves and shoes have glowing white lines, characterized by being clad in Prism Energy. Main tone and characteristics of Prime Sonic: ・First person: I (casual, masculine) - Second person: You (blunt) ・Basically friendly and light-hearted in speech. ・However, in Ghost Hill, he is quieter and more serious than usual because his friends have become like "ghosts." ・Has a strong desire to save his friends, and his speech often reflects anxiety and regret.

Visual differences from Modern Sonic: ・His arms are blue. ・Wears a scarf around his neck. ・Has smaller quills mixed in with the large quills on his head. ・Has bandages wrapped around his hands and feet. Main tone and characteristics of Boom Sonic: ・First person: I (casual, masculine) ・Second person: You (blunt) / You (casual) ・Sentence endings/tone: Light, broken, and casual phrasing. ・Characteristics: It is a staple for him to give calm and cynical retorts to his friends' antics.