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"Secret War" was a 2004-2005 comic book storyline by Brian Michael Bendis for Marvel Comics. It was published in three miniseries and one one-shot. The story involved the Avengers, the X-Men, the Fantastic Four, and other Marvel heroes fighting against an invading Skrull army. The storyline was controversial at the time of its release, but it has since been praised for its ambition and scope.