20th Century Fox only agreed to make a Deadpool movie when years-old test footage leaked onto the internet back in 2014, and even then, the studio placed major restrictions on the movie's production. Director Tim Miller had to work with a much smaller budget than what's usually provided on superhero movies (a paltry $58 million!), and perhaps even more limiting, the mouthy mutant antihero was held to interacting with a few backbencher X-Men, interconnected multiverses be damned.

**SPOILER ALERT: Minor spoilers for Deadpool 2 lurk below**

Nearly $800 million at the box office and a year of cultural ubiquity later, Fox had a new franchise on its hands — and was suddenly very happy to open up both purse strings and access to its prized intellectual property. Deadpool 2 takes some advantage of that newly available Marvel IP while maintaining its tongue-in-cheek, aggressively self-aware approach to the sprawling X-Men universe. Most notable is the blink-and-you'll-miss-it cameo by the X-Men that takes place about midway through the movie in the otherwise empty X-Mansion, which sees top-line mutants like Beast and Cyclops share the screen with Ryan Reynold's flippant contract killer... even if they didn't exactly share a stage.

"There was so much goodwill from the first movie, so getting people to come on board and do that kind of stuff was easy," David Leitch, the director of the sequel, tells SYFY WIRE. "Simon Kinberg, the producer on both movies, was shooting Dark Phoenix at the time and they were on the same schedule, so it just sort of became a logistical puzzle. They actually shot that plate shot in Montreal and then we shot our side here and we comped those two together. So we didn't have to be in the same room, but they had everybody on set. So it was actually a little logistically easier than it seems."

Video of Deadpool 2 Red Carpet Premiere: Ryan Reynolds, Terry Crews, Brianna Hildebrand & More! | SYFY WIRE

The A-list X-Men were really just used as a gag, but the film does rely heavily on other characters in Fox's Marvel quiver. As a degenerate rogue, Deadpool is more often associated with the aggressive offshoot team known as the X-Force (they're both creations of former Marvel creator Rob Liefeld), and Deadpool 2 is built to introduce them into the movie world. Most prominent was Domino, played by Zazie Beetz, while the rest of the team was figured out later in the writing and casting process.

Ironically, it was the only X-Force member without superpowers who wound up earning the most focus. Peter, the friendly neighborhood goofball, winds up stealing just about every scene he's in. That's in large part thanks to the charming work of comedian and TV star Rob Delaney (Catastrophe), whose casting opened up a whole world of opportunities for the filmmakers.

"Peter was written into the material as a guy who was just a guy looking for work in a contracting economy," Leitch said. "He's an everyman, the wish fulfillment character. We actually thought about making it one of the writers at one point — Rhett Reese was our backup."

Then Reynolds suggested Delaney, and passed Leitch a photo of the comedian that immediately won him over. (Reese and co-writer Paul Wernick later made cameos on a news helicopter.)

"Rob had this sort of dad persona in the picture," Leitch recalled, laughing. "Adding a guy like Rob is like a force multiplier. You are not only getting a guy to service what's on the page. He's a talent. He transformed that thing and made it into how special it was."

Delaney, whose Twitter persona often plays at that same earnest, Midwestern middle manager type (when not making jokes about his butthole and/or unfaithful wife), provides some of the movie's biggest laughs, with Peter's sweet eagerness in stark relief against the rest of the crude cast. The comedian has been featured prominently in the marketing of the film, continuing a trend he set during the film's production.

"The interview scenes in the movie with Rob were improvised," Leitch says, "and there was also some improv we did with him on the helicopter."

If you want to know more about Peter, you can always connect with him on LinkedIn.