Forget goats — the dark realm of Diablo III is being invaded by cows. In time for the role playing game's third anniversary, developer Blizzard is launching what it's calling a "cowpocalypse" in the game. From today until dusk on May 21st, it appears that players will be able to find secret cow portals that will take them to a level filled, naturally, with cows. As fans know, cows have a special relationship to the Diablo series, which makes Blizzard's choice of celebration as nostalgic as it is goofy. "We urge you all to stay calm and remember that cows don't kill people," the developer explains. "Everything else in Sanctuary kills people."