7.The shirt design is also a reference to Ryan Reynold's character in the movie Just Friends.
8.There's a few nods to Professor X, including a mention of Patrick Stewart.
9.Deadpool often jokes Batman more than once, and even delivers a Martha burn.
10.In one scene, Deadpool tries to calm down Juggernaut with the "Hey big guy, the sun's getting real low" bit from Avengers: Age of Ultron.
11.Brad Pitt made a funny and brief cameo as the X-Force member Vanisher after he walked away from the movie due to scheduling conflicts.
12.Matt Damon makes a cameo in the film alongside Alan Tudyk. In the scene when Cable first travels to the present timeline, Damon is one of the two rednecks sitting on the back of the pickup truck Cable steals.
13.And, even better, Damon is credited as "Dickie Greenleaf" — "Dickie Greenleaf" — the identity he steals from Jude Law in the 1999 movie The Talented Mr. Ripley.
14.Deadpool tells Cable to "Zip it, Thanos," because Josh Brolin plays both characters.
15.When Wade loses his mutant powers, he says he's just a useless guy with cancer — "Give me a bow and arrow, I'm basically Hawkeye,"
16.At one point, Deadpool yells at Cable to, "Give me your best shot, One-Eyed Willie!" which is a reference to Josh Brolin's first role in a film, Goonies.
17.Deadpool signs a cereal box with Logan's face (Wolverine) on it with "Ryan Reynolds."
18.When Deadpool needs help to take down Juggernaut, he stands outside Colossus' window with a stereo, a reference to Say Anything.
19.In the end credits, Deadpool has a device to go back in time. So he "fixes the timeline" by killing his first ever appearance as Deadpool in X-Men Origins: Wolverine.
20.And of course, he also kills Ryan Reynolds before he can accept the role of Green Lantern.