Sora's Final Form is earned a little differently compared to the others, as it first occurs randomly when Sora turns into a Drive Form after defeating Roxas in a mental battle near the beginning of the World that Never Was. Similar to Sora's Master Form, his Final Form wields two keyblades and emphasizes aerial maneuvers. Like his Master Form, most attacks and movements take place in the air--although his Final Form literally floats in the air the entire time. However, Sora's Final Form is more leaned toward physical power like his Valor Form, unlike his magic-bent Master and Wisdom forms. Both keyblades also float independently for maximum range and swing. This Form gains experience only with the destruction of Nobodies, so for Sora to build it up may be tricky, though easy spots tend to be found in the Castle that Never Was and Yen Sid's Tower. A possible theory as to how Sora attains this form is that Sora attained unity with Roxas's spirit.
Though turning into Final Form is completely random at first, once obtained it may be used like any other form other than Anti Form. Even then, Sora seems to be able to first acquire Final Form more frequently in the Underdrome than in other places.