Antiform

AntiForm (アンチフォーム) is one of Sora's Drive Forms in Kingdom Hearts II, which is a side-effect of using too much power. Sora gains the ability to transform into AntiForm at the same time he obtains Valor Form in Mysterious Tower.

Appearance
In most worlds, AntiForm makes Sora's skin and clothes turn black and blue, and white symbols are shown on the sleeves and front of the pants. His hands turn into claws and his eyes turn a bright yellow. Black and blue smoke billows from Sora's hands and back, that trails behind him as he runs. Sora is hunched over and constantly looks around when not in motion.