Deadpool Kills The Marvel Universe #1 by Cullen Bunn

Committed to a psychiatric facility by the X-Men, the merc with a mouth becomes the subject of a villain’s mind-control experiment that catastrophically backfires, snapping his psyche into a cold, meta-aware resolve. He kills his captor, escapes in a bloody rampage, and decides the only way to end the cycle of pain is to wipe out every hero and villain, launching the first shocking strikes of a universe-spanning massacre.

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