When "The Twilight Saga: Eclipse" comes out June 30, fans will see a much "darker, more animalistic" side of their beloved vampires and werewolves, according to co-star Jackson Rathbone. And since he is, actually, only human, Rathbone is grateful that he had a slight advantage in preparing for Jasper's battle scenes: his role in "The Last Airbender," which opens July 2.

"Well 'The Last Airbender' and 'Eclipse' are both action-heavy films, and I play characters [who are] a lot of the wars and a lot of the fight scenes," Rathbone told MTV News. "So, I did two months of kung-fu training for 'The Last Airbender' and then that actually parlayed really well going into 'Eclipse,' so I had all the background training."

But just because he had to get his kung-fu on for "Airbender," didn't mean he rested on his laurels once he got to the "Eclipse" set. "And then I did more fight training in 'Eclipse,' so I consider myself fairly well-trained — for film, at least. Don't come up to me on the street and try and fight me!"

Rathbone is happy that Jasper has a much more complex role in the third film than he did in "Twilight" and "Eclipse." "I play this very quiet kind of solitary character," he explained. "He's very dark and withdrawn, and now with 'Eclipse,' we get to see why. We get to go back into Jasper's backstory, who he used to be his old life and why he's afraid of himself around Bella. You get to see him warm up to Bella in this third film."

Check out everything we've got on "The Twilight Saga: Eclipse."

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