DEADPOOL co-writer Paul Wernick revealed to The Playlist some interesting information about what it took for 20th Century Fox to make a full-overhaul on Brianna Hildebrand’s Negasonic Teenage Warhead character.
“We were looking down the list of the 400 [‘X-Men’] characters that Fox owns, and NTW jumped out and we were like, ‘yes,’” said Wernick. “‘I don’t care what her powers are. She’s gonna be in the movie.”
In the comics, Negasonic (real name Ellie Phimister) is a gothic pre-cog with telepathy, but in the film, Wernick and Rhett Reese wanted to change a lot about the character, from her visual representation to her power-set. This required Fox to make a deal with Marvel.
“Kurt Russell [‘s Ego the Living Planet] in the new ‘Guardians [of the Galaxy Vol. 2]’ movie was the character that Fox swapped with Marvel to [change] Negasonic Teenage Warhead powers,” he explained.
Source: The Playlist