Sinister

A creature of the Modern Age born from the shadows of Marvel's beloved Age of Apocalypse mythology, Sinister made their catalog debut in 2005 courtesy of creator Tom Grummett. With appearances spanning two decades and a presence in handbook-style deep dives alongside Exceptional X-Men, this is a character for the dedicated Marvel scholar who loves unearthing the layers beneath the main continuity. Sharing pages with luminaries like Kitty Pryde and Bobby Drake, Sinister occupies a fascinating corner of the X-Men universe — rare enough to intrigue the completist, yet connected to some of Marvel's most iconic mutant storytelling.