Board Thread:Dark Souls II/@comment-90.220.93.142-20140316211638/@comment-24419193-20140317172945

Arvas134 wrote: It's never stated it is Ornstein but the Leo ring and the fact he looks like Ornstein makes it very likely that it is Ornstein. It could be that Ornstein was an Illusion in Dark Souls 1, afterall only Gwyndolin and the Darkmoon are still in Anor Londo.

Also, if you kill Gwynevere (or whatever it's spelt like) you'll find 2 knights outside the Ornstein & Smough boss room, a Berenike Knight and a Balder Knight. It could be that Gwyndolin allowed these two to take the ilusory form of Ornstein (Balder Knight) and Smough (Berenike Knight).

Probably, and the Gods left because they felt a great evil coming forth onto the land. If Orn lived, he would have to cling to Dark Magic to stay alive from being corrupted. Which would explain the changes in his armor and his spells that he casts.