He's playing a half-Apache enforcer
The plot (for those still unaware) finds a mysterious, amnesiac stranger (Craig) stumbling into a tightly controlled Arizona desert town known as Absolution. It’s not the friendliest place for outsiders and the situation is made worse by the cruel grip of Colonel Woodrow Dollarhyde.
Favreau has already begun making preparations for a summer shoot, and the movie should be invading our cinemas on August 5.
For more on the subject, see Green Lantern Out, Cowboys and Aliens In and COWBOYS & ALIENS.