Who directed the game in which George Newbern played Sephiroth? 
George Newbern:  He is also well known for his recurring role as Julia's son Payne in "Designing Women" and for providing the voices of Superman from the "Justice League" and "Justice League Unlimited" animated series, as well as Nooj and Sephiroth from the "Final Fantasy" series and the "Kingdom Hearts" series. Kingdom Hearts:  It is a collaboration between Disney Interactive and Square Enix, and is under the direction of Tetsuya Nomura, a longtime Square Enix character designer.
Tetsuya Nomura