Mark Ruffalo isn't the only Thor: Ragnarok star who had a chance to tackle the Hulk. According to Taika Waititi, the film's director, he occasionally stepped in to perform some motion capture for the big green guy. During a set visit, Waititi told Collider he did the mo-cap for the Hulk when Ruffalo was no longer on set.

"I’m playing one of the Planet Hulk characters: Korg, who’s a Kronan and a bit bigger than me. It’s all mo-cap. And often, since Mark [Ruffalo’s] no longer here, I’ll often jump in for Hulk’s stuff," he revealed. "We have stand-ins, but they’re not actors and they don’t have timing so I’ll jump in for those things."

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"I did Surtur as well, who will probably be re-voiced by someone else," he added. As revealed in July, Surtur will be voiced by journeyman actor Clancy Brown, who is known for his work on such projects as The CW's The Flash, Green Lantern, Spongebob Squarepants, Avengers Assemble and Star Wars Rebels.

Waititi began his film career as an actor in 1999's Scarfies, so the director is no stranger to the world of acting. He also starred in his vampire mockumentary What We Do In The Shadows and appeared in a small role in Hunt for the Wilderpeople, his most recent film. In Thor: Ragnarok, he will play Korg and the film's big bad Surtur as well as the Hulk.

Arriving November 3, director Taika Waititi’s Thor: Ragnarok stars Chris Hemsworth as Thor, Tom Hiddleston as Loki, Cate Blanchett as Hela, Idris Elba as Heimdall, Jeff Goldblum as Grandmaster, Tessa Thompson as Valkyrie, Karl Urban as Skurge, Mark Ruffalo as Bruce Banner/the Hulk and Anthony Hopkins as Odin.