Deadpool 2’s marketing has been relentless, so anything that was left out of the media onslaught was going to be a fun surprise by default. Anything that hadn't been done to death would be a breath of fresh air. But one of the major secret characters played a huge role in the movie and had some very surprising origins.
SPOILER WARNING: This article contains details about Deadpool 2, including info on a secret character and that character’s involvement with the plot. So see the movie first! (Unless you don’t care.)
So yes, we get Cable, Domino, and a nice grouping of X-Force members, but the major Marvel draw here was one we knew nothing about beforehand. The Juggernaut, the never-even-hinted-at X-Men villain, burst in to lend a bit of familiarity to the superheroic proceedings. But who was behind Professor X’s stepbro? The credits cite Juggernaut appearing “as himself,” which is hilarious but apparently untrue.
That’s because, according to CBR’s interview with Deadpool 2’s co-writer, Rhett Reese, Juggernaut’s facial motion capture and voice were provided by star/co-writer Ryan Reynolds.
“That was Ryan’s voice as the Juggernaut, and he did the facial capture for him,” said Reese, who adds that he wasn't actually sure how the physical motion capture happened — "I don’t think that was Ryan.” Juggernaut rather famously got the short end of the mutated stick in the original X-Men trilogy, where he was played by Vinnie Jones and was a bit underwhelming, so bringing the human wrecking ball back to the big screen during the film’s third act was a second chance.
“We committed to it pretty early on, because he’s never been done justice until now,” Reese said. “We always wanted to see a CG Juggernaut, so we finally got that. We also really needed to balance the scales in act three, between Deadpool and friends and little Firefist who has cool powers, but we needed to make it a fair fight. What greater force of nature than Juggernaut?" Reese said, adding, "It also gave us a chance for him to fight Colossus."
Juggernaut and Colossus have a historical comic rivalry, while the villain and Deadpool have had their own share of conflicts. Besides, what better way for a Deadpool movie to end than with Ryan Reynolds on both sides of the battle?