Die-hard Deadpool fans no doubt were extremely excited to learn, via a wall-breaking post-credits scene, that Deadpool 2 would introduce Cable. The son of Cyclops and Madelyne Pryor (a clone of Jean Grey... it's complicated), Cable comes from a distant future on thre X-Men timeline, which means time travel will be possible in the Deadpool universe now. There's a rich history to the Cable character, and he goes way back with Deadpool, only -- you won't have to know much of it, because the movie's making a major change to the character's comic origins. As Deadpool 2 co-writer Paul Wernick explains:
So with Cable, he's got such a convoluted past, and such a convoluted origin story that I think we're going to try to leave that, not mysterious, but there are a lot of twists and turns, cloning and all this stuff where you go, 'Oh my God. How do we get that across in a two hour movie?' I think we're going to distill him down to his essence. It will be authentic and faithful, but it's not going to include the 18,000 details if you were going to read a Wikipedia page about Cable you'd roll your eyes.
It's true that it's easier to introduce a character like Cable -- and explore his complicated backstory -- in the pages of a monthly comic book, where you explain how he has a bionic arm, and was infected with a techno-organic virus. He has had numerous adversaries over the years, but has been associated with teams like X-Force and The New Mutants. Later in the course of his publishing career, Cable was teamed with Deadpool, and it's probable that the sequel will build to that relationship.
It's intimidating because we have to find his voice, and we don't have an actor yet so we don't know who we're writing for. Most screenwriting happens without cast in place, but sequels it's a little bit different and it's likely that part will get cast, and we'll get to continue writing it and honing it for that actor, which I think is a good thing. There's been so many diverse people that have been brought up as possibilities for Cable, and who have not been brought up but we're considering. And that, much like with Ryan [Reynolds], that decision will greatly impact his cadences, his rhythms. And we'll certainly make him like he is in the comics, and we'll certainly be faithful, but I do think that voice will inform us quite a bit.
If they "distill" too much of Cable, though, we'll be extremely disappointed. Because he's a fascinating character, and if you are going to introduce him, you should take advantage of all of the cool reasons WHY you'd bring him into this universe in the first place.
Still, in Rhett Reese and Paul Wernick, we trust. We'll know more about their plans as Deadpool 2 rolls along toward production.