The X.S.E. (Xavier's Security Enforcers) concept was introduced by writer John Ostrander and artist Chris Bachalo. The team first appeared in "X-Men" #100 in 2000. First Appearances: The X.S.E. made their debut in "X-Men" #100 during the "X-Men: The Shattering" crossover event. They are a group of mutants from a dystopian future in the Marvel Universe. Major Comic Book Story Appearances: The X.S.E. played a prominent role in the "Bishop's Crossing" storyline, which explored Bishop's origins and the dystopian future from which he hails. The team also appeared in various other X-Men storylines. Full Bio: X.S.E. is a group of mutants from a dark future where the mutant-hunting Sentinel robots have decimated much of mutantkind. The team, led by Trevor Fitzroy, includes notable members like Bishop, who later travels back in time to prevent the dystopian future. The X.S.E.'s narrative is intricately tied to the concept of diverging timelines and the consequences of mutant persecution. Their appearance in the "Bishop's Crossing" storyline sheds light on the grim realities faced by mutants in their future timeline. Power Set: Members of the X.S.E. typically possess mutant abilities, reflecting a diverse range of powers. Bishop, for example, has the power to absorb and redirect energy, while other members exhibit various superhuman abilities. Friends and Allies in the Comics: The X.S.E. members, particularly Bishop, become allies to the X-Men when they travel back in time. Their interactions with the present-day X-Men add layers to the overarching narrative of mutant struggles and the impact of divergent timelines.