Blizzard Entertainment is celebrating Diablo III's third birthday with a special cow-themed in-game event.
The developer has introduced an Elite cow enemy named Herald of the Queen to the game on PC, Xbox One, and PlayStation 4.
Players who find and kill this enemy (people are reporting seeing the cow all over the place) will get to enter a portal that transports them to a location known as Not The Cow Level.
There, they will square off against even more angry bovines. The special cow level will remain available though May 21.
Xbox 360 and PlayStation 3 Diablo III players won't get experience the udderly weird level, but they can enjoy a 100 percent bonus for EXP and Gold through May 21, Blizzard explained in a post in its forums. This buff applies to the Ultimate Evil version of the game only.
For more on Diablo III's cow-themed birthday update--presumably a reference to Diablo II's secret cow level--you can read Blizzard's funny blog post and watch a pun-filled video on this page. Click the demon image above the "Forums" tab to launch the video.
Diablo III was released for PC on May 15, 2012. The game has gone on to sell more than 20 million copies.