Colossus got some tweaks for his big fight with Juggernaut, who makes a surprise entrance in the "Deadpool" sequel.

In “Deadpool 2,” Ryan Reynolds’ eponymous mutant antihero has his hands full with the cybernetic Cable (Josh Brolin), the teenage Firefist (Julian Dennison), and a surprise appearance by Marvel superbaddie, Juggernaut (also voiced by Reynolds).

But it’s really no surprise that the highlight is the climactic CG slugfest between mutant giant Colossus (again voiced by Stefan Kapicic) and the immense Juggernaut, who wears a protective steel helmet to prevent his stepbrother, Professor X, from infiltrating his mind.

Courtesy of 20th Century Fox

Preparing for the epic brawl were VFX studio Framestore Montreal (assisted by previs/postvis boutique, The Third Floor), with choreography overseen by director and former stunt coordinator David Leitch (“Atomic Blonde,” “John Wick”) and his stunt team.

First, Colossus had to get into shape. In the first movie, the metal giant was Frankensteined together with different facial and mocap performances. This time, he’s more unified. Kapicic’s facial capture and voice performance were simultaneous. Andrei Tricoteux again did mocap, and they built a helmet that could represent the Colossus’ on-set height for accurate camera positioning.

Additionally, Tricoteux wore gloves, a chest piece, and three strips of metal that ran down his arm from the helmet. The art department aged the accessories so they had the right weathered look. “Physically, we gave him a bit of a workout,” said Dan Glass, the production VFX supervisor. “He’s a lot more chiseled and angular.”

Courtesy of 20th Century Fox

Another animation improvement meant creating more believable flexing and punching by Colossus. The first movie used “live texturing,” which allowed for those iconic metal ridges across his arms. However, Glass wanted to do it with greater geometric precision, so Framestore animators provided a combination of shape movement and distortion for those really brutal blows.

For Juggernaut, the animators modeled his face on Leitch’s, creating a library of shapes and expressions. Reynolds provided both the voice and facial animation, which were greatly modified for the final performance.

“He needed to move convincingly, so we studied muscle builders walking and running,” said Glass. “The 6’8″ stand in also needed a helmet extension to provide full 9′ 6″ height so we had the right representation. We built his helmet full scale so a stunt guy could climb on top of it during the struggle for reference.”

Courtesy of 20th Century Fox

It was a challenge for Framestore to animate the helmet in a way that provided enough room for the character to move its head and have it work with the rig underneath, which controls Juggernaut’s complex muscle system.

As for the fight choreography, the director wanted a visceral, brutal brawl, in which Juggernaut bashes Colossus’ face and knocks out a tooth before sustaining physical damage himself. “We had two stunt players that were comparable to the height differential,” Glass said. “Dave was able to work live and interactively with them and do the beats that we wanted in a mocap stage. We then fed that into post-vis that we could lay together, and then timed it and built to camera.”

Key to the brawl was having the straight-laced Colossus fight dirty because he’s so overmatched. “He grabs the fence post and stabs him in the eye and the groin,” added Glass. “He gets down to Deadpool’s level.”

Sign Up: Stay on top of the latest breaking film and TV news! Sign up for our Email Newsletters here.