The events of Marvel ComicsAvengers vs X-Men were some of the most dramatic conflicts that the Earth’s Mightiest Heroes and its Merry Mutants have gone up against. While the heroes of the Marvel Universe are no strangers to Civil Wars, the global scale to which the conflict spread changed the relationship between two of the publisher’s most popular teams in a way that has never fully been prepared. And while many of the heroes may not realize it, it’s all thanks to one man – Mister Sinister.

Also known as Nathaniel Essex, Mister Sinister has been a thorn in the X-Men’s side for quite some time. But when his usual power-mad antics found him toying with the fate of the Phoenix, the crazed eugenicist set his sights toward manipulating the Avengers as well. And as things often go for Mister Sinister, his plans didn’t come to fruition the way he’d anticipated.

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Avengers vs X-Men Has Sinister To Thank

Mister Sinister Hope Sumers

Uncanny X-Men #14 by Kieron Gillen and Dustin Weaver finds Sinister speaking to one of his many clones about his recent clashes with the X-Men and his ongoing machinations, and while detailing his plans, he states, “I prompted little Hope Summers’ development. I knew that the Avengers wouldn’t let the Phoenix possess the girl. I knew it would find hosts elsewhere,” before revealing a half dozen newly created clones of Madelyne Pryor to serve as the Phoenix’s new hosts and fuel his depraved idea of civilization. Essex’s plans eventually come undone when faced with the newly empowered Phoenix Five in Uncanny X-Men #17 by Gillen, Daniel Acuña, and Mike Del Mundo as Sinister’s own vanity prevents him from comprehending the idea of a power beyond his control.

Unfortunately for Nathaniel, this habit of biting off more than he can chew has become something of a pattern. After all, his control of Dark Web's Madelyne Pryor was nowhere near as absolute as he believed, leading to the events of Inferno by Chris Claremont, Louise Simonson and more. And even more recently than his fumble with the Phoenix, his schemes surrounding the Hellions on Krakoa proved far more difficult to manage than he originally intended.

Mister Sinister Doesn’t Know How to Win

Mister Sinister Phoenix

Mister Sinister is undoubtedly a brilliant man, but his own ego ensure that he’ll always stand in his own way. And with the upcoming Sins of Sinister event by Gillen, Al Ewing, Si Spurrier and more on the horizon, it seems this ego is now putting the entire Marvel Universe at risk. And it’s only a matter of time before the X-Men will have to pick up the pieces he leaves behind.

Mister Sinister may be one of the Marvel Universe’s most devious scientific minds, but his sense of strategy could use quite a bit of work. Time and again, Essex’s schemes have blown up in his face, more often than not leading to quite a bit of bloodshed. And with Sins of Sinister on the way, Marvel Comics’ X-Men better be ready to deal with whatever mess Mister Sinister generates this time.

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