A Fragmentary Passage

Zero point, also referred to as the Secret Episode (シークレットエピソード), is a secret ending exclusive to Kingdom Hearts Birth by Sleep Final Mix. Unlike other secret endings, Zero point is playable, much like the Final Episode, rather than simply watching from the view of a bystander.

In Zero point, Aqua is playable, the main setting being the Realm of Darkness, where Aqua fights several Pureblood Heartless while wielding Eraqus's Keyblade.