Metal Sonic 4.0 is a new character in Super Mario Silver Spurs 2: Adventures Beyond. He is built by Fawful and Eggman Nega to destroy Mario and his friends and acquaintances. But he ends up focusing more on Metal Sonic 3.0's issues, thus becoming his rival.
|Mario | Gumball Watterson | Bowser | Sonic the Hedgehog | Darwin Watterson | Miles "Tails" Prower | Luigi | Bowser Jr. | Kirby | Finn the Human | Jake the Dog | Mordecai | Rigby | Pikachu | Ash Ketchum | Cilan | Iris | Dawn | Maylene | Steve | Creeper | Pac-Man | Knuckles the Echidna | Meta Knight | Eclipse the Hedgehog|
|Wario | Shadow the Hedgehog | Waluigi|
|Count Bleck | Metal Sonic 4.0 | Metal Sonic 3.0 | Mecha Sonic II | Dark Gaia | Magolor | Time Puncher | Demise | Ridley | Darkai | Galacta Knight | Boom Boom | Pom Pom|
|Cosmic Clone Mario | Cosmic Clone Gumball Watterson | Cosmic Clone Bowser | Cosmic Clone Sonic the Hedgehog | Cosmic Clone Darwin Watterson | Cosmic Clone Miles "Tails" Prower | Cosmic Clone Luigi | Cosmic Clone Maylene | Cosmic Clone Steve|
|Unova | Green Hill region | Highway View | Dimension World | The Dark Vortex world|