This game features the debut of Flare The Hedgehog
In a small capsule under Eggman's Base, Sinister laughing is heard, then sirens go off, Decoe, Bocoe and Metal Sonic Run around with net guns, and Tails Doll and Metal Knuckles are closing all the exits, and the sinsiter laughing continues, the object breaks out and begins to cause havoc!
Sonic has the most stages of any character, and his levels involve high speed gameplay. His story involves Flame kidnapping Amy.
Most of his levels are abridged versions of Sonic's, which require him to reach the end of the level before Sonic (or Eggman) can. His Story Involves Eggman hacking into the Tornado's Hardrive.
His stages are enclosed areas where Knuckles must find shards of the Master Emerald. He can glide through the air and scale most walls. His story involves Flare taking the Master Emerald and breaking it.
AmyHer primary weapon, the Piko Piko Hammer, returns. Amy is considered to have the shortest story since she has fewer levels than the other characters. Despite their length being second only to Sonic's. Her story involves Birdie getting kidnapped by Zero.
His levels involve using his fishing pole to try and catch Froggy, although he can also choose to try and catch big fish, with score bonuses based on size. His story involves Froggy getting possesed by Flare and Big has to save him.
DecoeDecoe's Missions involve finding robots for Eggman, and they are usually in areas like Knuckles, His story involves Eggman's Army getting kidnapped and scattered by Flare.
ShadowShadow's missions are like spy missions, He gets missions from G.U.N and has to carry them out, his story involves Omega's battery being taken by Flare.
(Currently No Pic) Bean's levels take place in areas with lots of enemies, his story involves Flare melting the Ice Cap with Bark still on it.
VectorVector's Levels are like Knuckles' and Decoe's combined, after Eggman's base explodes, The Chaotix have to find robot parts and take them back to demented doctor, and get paid!
- Jet - Sonic
- E-102 Gamma's Ghost - Tails
- Rouge - Knuckles/Shadow
- Cream - Amy
- Birdie - Amy
- Froggy - Big
- Fang - Big
- Bocoe - Decoe
- Robot Doppelgangers of Team Sonic - Decoe
- Omega - Shadow
- Bark - Bean
- Honey - Bean
- Blaze - Bean
- Espio - Vector
- Charmy - Vector
- Mighty - Vector
- Flare - All
- Dr. Eggman - Tails
- Zero - Amy
- Silver - Vector
- This is Decoe and Bocoe's first game appearance.
- YoshiEgg Nook was a character possibility, but was scrapped.
- Flare is the result of Dr. Eggman trying to make a hamburger on his grill, which was plugged into the hedgehog maker.
- Perfect Flare was originally less scary looking.
- Bokkun and Coconuts were planned as NPC's.
- This is the first Sonic Adventure to not feature Tikal.