Warning: There are major spoilers below for "Deadpool 2."
"Deadpool 2" has a few surprise cameos, but its biggest surprise came about halfway through the movie when it brought back an old "X-Men" character we didn't expect to see again.
This is your last chance to head back before spoilers.
When Deadpool and Russell are sent to a prison in Canada for mutants, they hear that there's one special mutant hidden away because he's too dangerous.
Deadpool eventually escapes the prison, but goes to save Russell while in transit to another safe holding. Naturally, Russell isn't the only mutant stowed away on board a massive cargo truck. When the truck eventually crashes, Russell breaks free, but so does the mysterious mutant we were warned about earlier in the movie.
Out steps a very large man with a cement block on his head who fans will recognize as the Juggernaut.
Who is Juggernaut?
If you were among the people in the theater cheering in excitement when Juggernaut appeared on the screen, it was probably because X-Men fans thought we may never see him again on screen.
Cain Marko appeared once before on screen, in 2006's "X-Men: The Last Stand." He was a member of Magneto's Brotherhood of Mutants. You probably remember him for reciting the line, "I'm the Juggernaut, b--ch!" after getting trapped momentarily in the floor by Kitty Pryde.
Juggernaut's main power is superhuman strength and speed. How strong is he? He could run through buildings without any problem or getting tired. He was first introduced in 1965's X-Men #12 as Charles Xavier/Professor X's bullying stepbrother.
In some of the comics, he also had some mystical powers, but movie adaptations have stuck to playing off his immense strength.
Will we see Juggernaut again?
It's definitely possible. He is Charles Xavier's stepbrother after all and he's one of the most important mutants.
At the end of "Deadpool 2," Colossus and Negasonic Teenage Warhead leave Juggernaut at the remains of the Essex House as he's still being electrocuted.
It will take a lot more than that to do Juggernaut in. Since the group doesn't leave him dead, he's now on the loose out in the "X-Men" universe somewhere.
You can follow along with our "Deadpool 2" coverage here .
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