Vanitas

"The Terra you knew will be gone forever." - Vanitas to Ventus

Vanitas (voiced by Haley Joel Osment) is Master Xehanort's evil apprentice and is the darkness of Ventus' heart. Vanitas also is the source of the Unversed. Most of the time, he is seen with a mask on, but without it, he looks exactly like Sora. This is due to Sora's heart connecting with Ventus' heart, Vanitas would look like that person. His plot was to make Ventus strong enough so that they would merge and create a powerful weapon called the x-blade. Even though he was successful, he was defeated by Aqua and King Mickey Mouse in a physical battle, and by Ventus in a metaphysical battle.

He is part of the Heylin side, and Twilight has a huge grudge on him for were against her best friends Aqua.