The X-Men will officially debut in the Deadpool 3 movie and eventually cement themselves as a superhero group within the Marvel Cinematic Universe. But what villains should they introduce alongside them? The obvious choice would be Magneto, as there has been a long-standing feud between him and the X-Men in the comics and in all the live adaptations. Another obvious choice would be the Sentinels, as they have shown to be the greatest threat against the mutants.
Source：https://www.cbr.com/xmen-orchis-next-mcu-villains/
