‘Marvel Universe Live! Age of Heroes’ characters enter the 3-D realm at Barclays

Fashioning costumes for iconic superheroes is challenging enough. But Mark Koss also had to bring to life a treelike animated creature that had captured the heart of millions on the big screen.

He could not use special effects and motion-capture technology to create the towering character Groot, a member of the Guardians of the Galaxy, for the “Marvel Universe Live! Age of Heroes” show.

“How do you take a costume that is supposed to be made of wood and make it malleable so you can go into battle?” said Koss, costumer designer for the show, who lives in Brooklyn. “The whole costume is painted fabric and foam that looks like wood. It’s pretty incredible how it can move so easily and look like this hardened piece of wood.”

Recreating Groot’s soulful, dark eyes also took a bit of finesse.

“His eyes are so expressive in the movies but we couldn’t figure out how to do that and allow the performer to see under the stage lights,” Koss said. “So we had to give and take.”

“Marvel Universe Live!” comes to the Barclay Center on Feb. 22, with a special preview at Grand Central Terminal on Feb. 21 from 10 a.m. to 7 p.m. Underneath all of the colorful, flashy costumes is months of work — and usually a harness.

“It’s all about trying to create magic for kids and their parents,” said Koss.

This is his second time working with the “Marvel Universe Live!” show and the first time he oversees all the costumes.

“I’ve always had an interest in telling a story through clothing,” said Koss, 31, who grew up in California and received his graduate degree at the NYU Tisch School of the Arts.

Koss worked on a number of theatrical shows in California and New York. But becoming part of the Marvel Universe was a whole new experience.

The show includes a bevy of Marvel heroes from Captain America and Iron Man to the Hulk, Thor, Black Panther, and of course the other Guardians of the Galaxy.

Koss and his team were determined to put together something special for the character of Rocket, a hard-charging raccoon and Groot’s BFF.

“We padded out his body so it’s a different shape,” he said. “We didn’t want the audience to feel like they were watching a 5-foot tall human.”

They played with hinges and other devices to make sure his bushy tail moved but didn’t get in the way of the action.

Many of the costumes had to be altered to hide harnesses and technology — such as Spider-Man’s laser web shooter.

“We had a huge army of people working on this show,” Koss said. “Our team built these clothes but the actors had to make them come alive. When you see it in the arena space it feels explosive. You feel connected to all these people and you are rooting for them.”

If you go: “Marvel Universe Live!: Age of Heroes” runs from Feb. 22-25 at Barclays Center, 620 Atlantic Ave., Prospect Heights, barclayscenter.com

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