Colossus Bat

Colossus Bat is the (tentative name for the) transformation device & partner to Kamen Rider Colossus. Colossus Bat is a mechanical Vampire Bat created by the Legendorga for their leader to assume his rider form. When Kamen Rider Colossus uses the Wake Up Fuestle (which resembles Blizzard's Key Fuestle), Kamen Rider Colossus transforms to Legend Colossus & Colossus Bat also assumes Mecha Bat mode as his persona cast comes off & yells, "Die."

Personality
In the short amount of time he was seen talking, Colossus Bat is cheerfully sadistic, taking delight in destroying enemy.