WARNING: The following contains SPOILERS for Uncanny X-Men #18
Nathaniel Essex AKA Mister Sinister has always been one of the X-Men's greatest villains, expanding his powers and abilities through genetic experimentation. But his latest breakthrough just made him the X-Men's BIGGEST villain (quite literally).
In Uncanny X-Men #18, Sinister not only turns people into actual copies of himself (which Multiple Man points out trespassing into his power set), but has apparently learned how to absorb them into his body. Yes, we really do mean into his body, making him a giant threat.
It all starts when the X-Men engage in battle with the Marauders, some of Mister Sinister's proteges. Hope Summers is faced with no other choice than to take one of them out--permanently. One of their own, Chamber AKA Jonothon Starsmore gets seriously injured in the fight and is in need of immediate attention. Magik transports the team home to Harry's Hideaway, only to discover Mister Sinister has beaten them there. That's not all: he's set it on fire, and is burning it to the ground by the time they arrive.
Juggernaut rushes in to save any members of the team that might be inside, when they realize Chamber is gone ("His energy just...went out"). Mister Sinister takes advantage of the mourning X-Men, and attacks. That's when he calls his 'Sinister Fire Brigade,' composed of a dozen copies of himself that h e can switch his consciousness between to keep one step ahead of his enemies.
Before they attack, the X-Men wonder if there are real people under there, or if Sinister has created the clones without innocent casualties. Maddox points out that given their experiences with Sinister, "if they were real people, they're gone now." The team might regret this moment of hesitation to attack the Sinisters down the road... because that's the moment they all merge into the prime Mister Sinister to create one giant-sized foe. Alex Summers AKA Havok has finally had enough of this returned foe, and channels everything he has into taking down the bigger, better, badder Mister Sinister. And in the end, pulls it off quite easily.
Not only does the blast of power bring him back to normal size, but with his brilliant plan so easily bested, he instantly surrenders. Which all seems a little... too simple. There seems to be a larger plan at work, which may explain why the final page of the issue reveals things are all proceeding as Emma Frost expected. Can fans assume Mister Sinister is part of it? If so, he at least got the see what it feels like to be bigger than the X-Men, even if he still can't be better.
Uncanny X-Men #18 is on sale now from Marvel Comics, and at your local comic shop.