|Boss(es)||Egg Nega Wisp|
|Preceded by||Aquarium Park, Planet Wisp, or Asteroid Coaster(depending on player's choice)|
|Proceeded by||None, Final Level|
Terminal Velocity is the final stage in Sonic Colors. This stage connects Earth to Eggman's Amusement Park in space. Sonic and Tails notices how Eggman's Amusement Park is about to collapse, so they decide to run through the Terminal Velocity stage in order to reach the space elevator, allowing them to head back to Earth.
 Wii version
 Act 1
Sonic runs down a straight pathway for the entire Act. It starts out with Sonic being chased by three Aero Chasers that emit lasers, which Sonic has to avoid using Quick Step. He also have to jump over small hurdles while dodging the lasers. The next section has Sonic running alongside Motobugs, which Sonic can easily defeat by boosting or quick atepping into them. Defeating them, will fill his boost gauge. Finally, a large purple badnik, who also appeared in Aquarium Park, will chase Sonic from behind and attempt to attack with his hands if he's close ranged or his lasers if long ranged. While Sonic is avoiding this badnik, more Motobugs will appear to try and take Sonic out. After a few seconds of avoiding all of the enemies, the Act will end.
 Boss Battle
Egg Nega Wisp serves as the boss of Terminal Velocity and is the final boss in the Wii version of the game. Sonic and Tails finally reach the elevator to escape the Amusement Park, but Eggman stops them. He introduces them to the Egg Nega Wisp, which he explains is powered by the energy of the Wisps that Sonic has encountered during his adventure. After they exchange words, Sonic quickly shoves Tails into the elevator, sending him back to Earth safely, while he prepares to take on Eggman one final time.
 Act 2
This is the final act of the entire game and it only lasts a few seconds. After Sonic defeats Eggman, the Amusement Park starts to crumble and a black hole starts to engulf everything. Sonic starts to run down a straight pathway once more to avoid getting engulfed himself. In this brief running segment, you simply have to jump or Quick Step to avoid the bottomless pits.
Despite that, Sonic will still fail to outrun the black hole, get sucked in and become unconscious, but the Wisps will safely carry him back to Earth.
 DS version
 Act 1
Sonic and Tails reach the elevator, where Sonic tells Tails to head inside and make his way back to Earth, which he agrees. Sonic notices a black hole, so he decides to escape while Eggman chases him.
This is the only Act of Terminal Velocity in the DS version. It's another short level that is about one minute long which, similar to the Wii version, has Sonic running down a straight pathway. In this version, there are no common enemies that get in Sonic's way, although the tail of the Egg Nega Wisp(Nega Armor Wisp in the DS version) will attempt to attack Sonic from behind.
 Boss Battle
As with the Wii version, the boss battle of the Terminal Velocity is the Nega Armor Wisp and is the penultimate boss of the DS version of the game. The design is slightly different, in that the machine only has a tail, instead of the two tentacles in the Wii version. Also the battle takes place on a small platform, while the environment around him starts to crumble.
- Terminal Velocity has the least amount of Acts in both versions.
- This level lacks checkpoints as well as the 2D segments.
- In the Wii version, it's the only level that has an Act, following a Boss Battle.