Matt Damon Hasn't Heard Ben Affleck's Batman Voice

We've heard Ben Affleck's modulated Batman voice, but in each instance he's been wearing his [...]

We've heard Ben Affleck's modulated Batman voice, but in each instance he's been wearing his heavy duty armor. We still don't know what Affleck sounds like with Batman's regular cape and cowl on. That's okay though, neither does his best buddy, Matt Damon.

"I haven't heard the Batman voice yet!" Damon told MTV while promoting his new movie The Martian at the Toronto International Film Festival.

Damon may not be privy to the Bat-voice but he was one of the select people Affleck consulted with before deciding to play the Caped Crusader in Zack Snyder's Batman v Superman: Dawn of Justice. "I talked to him about it. It was a big decision," Damon remembered. "He knew what the stakes were. Once he was able to get Chris Terrio to write the script, I think that made the decision for him. Chris is a fantastic writer and Ben really liked Zack [Snyder], who's directing, and it was like, 'well, I've got all the pieces that are necessary.'"

Damon seems most impressed with how quickly Affleck was able to pack on the muscles for his superhero physique. "He put on like 30 pounds, which took him like nine months," Damon explained. "He put on like 30 pounds of muscle, which is really not easy to do. You've gotta eat a lot. You've gotta be an omnivore. Or just greedy."

In Batman v. Superman: Dawn of Justice, fearing the actions of a god-like Super Hero left unchecked, Gotham City's own formidable, forceful vigilante takes on Metropolis's most revered, modern-day savior, while the world wrestles with what sort of hero it really needs. And with Batman and Superman at war with one another, a new threat quickly arises, putting mankind in greater danger than it's ever known before.

Batman v. Superman: Dawn of Justice opens March 25, 2016.