Avengers vs. X-Men (AvX or AvsX) is a 2012 crossover event that was featured in comic books published by Marvel Comics. The event, consisting of an eponymous limited series and numerous tie-in books, involves the return of the Phoenix Force and the subsequent war between the Avengers and the X-Men. The 12-issue twice-monthly series was first published in April 2012, and features a storyline by Jason Aaron, Brian Michael Bendis, Ed Brubaker, Jonathan Hickman and Matt Fraction, with a rotating team of artists including John Romita Jr., Olivier Coipel and Adam Kubert. The event was preceded by the four-issue limited series Avengers: X-Sanction by Jeph Loeb and Ed McGuinness and Avengers vs. X-Men #0. Avengers vs. X-Men also ties into the limited series AVX: VS, described as "the fight book" which expands upon many of the one-on-one battles featured in the main series, the digital series; Avengers vs. X-Men: Infinite, and into a number of ongoing series including Avengers, Avengers Academy, New Avengers, Secret Avengers, Uncanny X-Men, Wolverine and the X-Men and X-Men: Legacy. The event was succeeded by the limited series AvX: Consequences. Despite receiving mixed reviews from critics, Avengers vs. X-Men was a commercial success that topped the comic-book sales charts for several months, from April to October 2012. The repercussions of the storyline resulted in the new status quo of the Marvel Universe presented in the company's Marvel NOW! relaunch initiative. Source: Wikipedia (en)