Cannonball foi originalmente planejada para o filme porque, para citar Tim Miller
"In the original script the action in the third act was great, but it was just Deadpool and a lot of guns
Mas eles estavam preocupados com ele sendo visto como um caipira:
"We thought about Cannonball, but he would’ve been a stupid hick character, whereas the guys wrote Negasonic as this deadpan goth teen, which was a great angle.
Eles escolhem o personagem baseado no nome e combinam os poderes:
I went through the list of Marvel characters ... And at the end of that list was Negasonic, which I just thought was a freaky, funny name.