Nintendo/Sonic Adventure 2 (2001)

Cast:
 * Mario/Fire Mario (from Mario) as Sonic/Super Sonic
 * Ness (from EarthBound) as Tails
 * Donkey Kong (from Mario) as Knuckles
 * Captain Falcon (from F-Zero) as Shadow/Super Shadow
 * Bowser (from Mario) Dr. Eggman/Dr. Robotnik
 * Sheik (from The Legend of Zelda) as Rouge
 * Peach (from Mario) as Amy
 * Metal Mario (from Mario) as Metal Sonic
 * Jigglypuff (from Pokèmon) as Tikal
 * Samurai Goroh (from F-Zero) as Chaos 0
 * Rosalina (from Mario) as Maria
 * Wolf O'Donnell (From Star Fox) as Professor Gerald Robotnik
 * Olimar (from Pikmin) as Omochao
 * Mr. Saturn (from EarthBound) as Hero Chao
 * Bob-Omb (from Mario) as Dark Chao
 * Pokè Ball (from Pokèmon) as Regular Chao
 * Ridley (from Metroid) as Big Foot
 * Piranha Plant (from Mario) as Hot Shot
 * Morton Koopa (from Mario) as Flying Dog
 * Iggy Koopa (from Mario) King Boom Boo
 * Giga Bowser (from Super Smash Bros. Series) as Egg Golem
 * King K. Rool (Donkey Kong) as Biolizard
 * Bulblord (from Pikmin) as Finalhizard

Bosses

Hero Story

Mario (from Mario) as Sonic
 * Ridley (from Metroid) as F-6t Big Foot
 * Bowser (from Mario) as Dr. Eggman/Dr. Robotnik #1 (Ness) from Earthbound) (as Tails)
 * Captain Falcon (from F-Zero) as Shadow #1 (Mario) (from Mario) as Sonic
 * Iggy Koopa (from Mario) as King Boom Boo (Donkey Kong) (from Mario) as Knuckles
 * Giga Bowser (from Super Smash Bros. Series) as Egg Golem (Mario) (from Mario) as Sonic
 * Sheik (from The Legend of Zelda) as Rouge (Donkey Kong) (from Mario) as Knuckles
 * Bowser (from Mario) as Dr. Eggman/Dr. Robotnik #2 (Ness) (from Earthbound) as Tails

Dark Story
 * Piranha Plant (from Mario) B-3x as Hot Shot (Captain Falcon) (from F-Zero) as Shadow
 * Ness (from Earthbound) as Tails #1 (Bowser) (from Mario) Dr. Eggman/Dr. Robotnik
 * Donkey Kong (from Mario) as Knuckles (Sheik) (from The Legend of Zelda) as Rouge
 * Ness (from Earthbound) as Tails #2 (Bowser) (from Mario) as Dr. Eggman/Dr. Robotnik
 * Mario (from Mario) as Sonic #2 (Final) (Captain Falcon) (from F-Zero) as Shadow

Final Story
 * Mollusque (Captain Falcon) (from F-Zero) as Shadow
 * Bulblord (from Pimkin) as The Finalhizard (Fire Mario (from Mario) as Super Sonic and Captain Falcon (from F-Zero) as Super Shadow

Stages

Hero Story 1. City Escape (Mario) (from Mario) as Sonic 2. Wild Canyon (Donkey Kong) (from Mario) as Knuckles 3. Prison Lane (Ness) (from Earthbound) as Tails 4. Metal Harbor (Mario) (from Mario) as Sonic 5. Green Forest (Mario) (from Mario) as Sonic 6. Pumpkin Hill (Donkey Kong) (from Mario) as Knuckles 7. Mission Street (Ness) (from Earthbound) as Tails 8. Aquatic Mine (Donkey Kong) (from Mario) as Knuckles 9. Route 101 (Ness) (from Earthbound) as Tails 10. Hidden Base (Ness) (from Earthbound) as Tails 11. Pyramid Cave (Mario) (from Mario) as Sonic 12. Death Chamber (Donkey Kong) (from Mario) as Knuckles 13. Eternal Engine (Ness) (from Earthbound) as Tails 14. Meteor Herd (Donkey Kong) (from Mario) as Knuckles 15. Crazy Gadget (Mario) (from Mario) as Sonic 16. Final Rush (Mario) (from Mario) as Sonic

Dark Story 1. Iron Gate (Bowser) (from Mario) as Dr. Eggman/Dr. Robotnik 2. Dry Lagoon (Sheik) (from The Legend of Zelda) as Rouge 3. Sand Ocean (Bowser) (from Mario) as Dr. Eggman/Dr. Robotnik 4. Radical Highway (Captain Falcon) (from F-Zero) as Shadow 5. Egg Quarters (Sheik) (from The Legend of Zelda) as Rouge 6. Lost Colony (Bowser) (from Mario) as Dr. Eggman/Dr. Robotnik 7. Weapons Bed (Bowser) (from Mario) as Dr. Eggman/Dr. Robotnik 8. Security Hall (Sheik) (from The Legend of Zelda) as Sheik 9. White Jungle (Captain Falcon) (from F-Zero) as Shadow 10. Rouge 280 (Sheik) (from The Legend of Zelda) as Rouge 11. Sky Rail (Captain Falcon) (from F-Zero) as Shadow 12. Mad Space (Sheik) (from The Legend of Zelda) as Rouge 13. Cosmic Wall (Bowser) (from Mario) as Dr. Eggman/Dr. Robotnik 14. Final Chase (Captain Falcon) (from F-Zero) as Shadow

Final Story

1. Cannon's Core (Ness from Earthbound as Tails Bowser from Mario as Dr. Eggman/Dr. Robotnik Sheik from The Legend of Zelda as Rouge Donkey Kong from Mario as Knuckles and Mario from Mario as Sonic)

Extra Stage 1. Green Hill (Mario) (from Mario) as Sonic