1) Marauders
From the Comics: If Warner Bros. can have a whole movie dedicated to the super-villains of the Suicide Squad, then why not give a film to the murderous mutants of the Marauders? Brought together by the evil mutant Mr. Sinister for a mysterious purpose, the Marauders attacked the mutants living in the tunnels underneath New York and would later try to kill several key X-Men. For an added twist, Marauders seemingly killed in action are brought back from the dead for their very next mission. There’s probably so fun that can be had with that…
Connection to the Film Series: Two Marauders have already appeared in the X-Men series of films. One is Sabretooth, Wolverine’s nemesis who was played by Tyler Mane in X-Men and Liev Schreiber in X-Men Origins: Wolverine. The other is Riptide, who in X-Men: First Class is seen as one of Sebastian Shaw’s lackies in the Hellfire Club. In another bit of comic book trivia, it was revealed that Mr. Sinister used a broker to bring the Marauders together, and it was none other than Gambit, who will appear in his own solo movie next year and be played by Channing Tatum.
Adaptation: A Marauders movie could go in many possible directions, like a straight up evil version of the X-Men where we see the bad guys be a scourge to mutantkind, or it can focus on Mr Sinister’s weirdo fascination with the Summers family, including Cyclops and Havok. Although Magneto and his Brotherhood have been frequent X-Men adversaries, their actions are somewhat sympathetic given humanity’s hatred of mutants, but the Marauders are just straight up evil, and making a movie about them could shed some light on the darker side of the mutant world that has yet to be seen on the big screen.