4. Christoph Waltz
The Weinstein CompanyChristoph Waltz may only be known to English-speaking moviegoers for his performances in Django Unchained and Inglorious Basterds, but theres a reason he won best supporting actor Oscars for both films. Whether its the SS officer Hans Landa or dentist-turned-bounty hunter Dr. King Schultz you prefer, Waltzs performances in both were outstanding. He could very convincingly play a character similar to BioShocks Frank Fontaine/Atlas, and his ability to switch between a warm, caring personality to one of malice and cruel intent would work wonderfully in a video game world. He doesn't have to play a dual personality character though. If Waltz were to borrow some qualities from his Dr. Schultz character, he could easily play the part of a mentor or companion that the player forms an emotional attachment to.