Shadow Form

Temporary form
Sora turned inta a shadow heartless after his fight with Riku. He is only in this form briefly and can only jump. However, due to Kairi's heart, he is able to recover into his human form again. Since he was a Heartless, albeit temporarily, he created a Nobody that became known as Roxas.

Drive Form
Sora can become Shadow Form randomly when taking a Drive Form using 1 or 2 of his partners. in the background, a gauge runs up everytime you use an other form. I don't know the exact amounts, but it's around this 0-5 uses: 0% chance 5-10 uses: 10-20% chance 10-15 uses: 30-40% chance 15-20 uses: 60-75% chance

in this form, Sora goes running on hands and feet, his combo finish changes, his defense lowers, his speed ascends a bit, has no Keyblade and cannot use magic.