ILM President Lynwen Brennan teased fans about The Hulk’s storyline in “Avengers: Age of Ultron” during an interview with IGN.

Industrial Light & Magic (ILM) is responsible for creating CGI effects on many Marvel and Lucasfilm productions, but Brennan explained Mark Ruffalo’s character in “Avengers: Age of Ultron” was their biggest challenge yet.

“As usual ILM does some of the harder work that isn’t out there in the trailers, so I can’t talk about much. But obviously the Hulk is in there, and he’s a really big creative challenge for us,” Brennan told IGN.

Brennan teased The Hulk has gone through an evolution in the second “Avengers” installment, and the studio wanted to reflect the hard work Ruffalo put in to creating the character.

“Getting that personality is very important to Joss [Whedon], and it’s very important that it’s driven by Mark [Ruffalo]’s performance,” she told IGN. “We’ve developed a new capture system, which we call Muse, which really captures the actor’s performance - it allows us to combine different takes as well. We’re using it on Warcraft, and we furthered the development on Avengers.”

Brennan also spoke briefly about Lucasfilm’s upcoming “Star Wars: Episode VII.” The ILM president teased J.J. Abrams’ unique vision comes to life in the film and many fans of the franchise will enjoy the latest installment.

“It’s very much JJ [Abrams]’s style, we’ve worked with JJ quite a few times now,” Brennan said. “One of the things that makes his films have so much heart is they are grounded in reality. There’s something the actors can touch and feel. He’s so passionate about that, and it comes through in his films.”

“Avengers: Age of Ultron” is set to hit theaters on April 24, 2015. “Star Wars: Episode VII” will be released on December 18, 2015.