One of the more well known aspects of Diablo 2 Items was something that didn't actually exist.

One of the more well known aspects of Diablo 2 Items was something that didn't actually exist. Rumors started of a "cow level" with varying instructions or ideas on how to enter such a place and what existed in this level.

Blizzard put a cheat code in StarCraft: 'there is no cow level.' Typing cheat results in an instant victory of the game.

The Hellfire expansion gives a tongue-in-cheek nod to this rumor: if cowquest is added to command.txt, the Farmer's Orchard quest is replaced by a Cow Quest. Lester the Farmer is replaced by a Complete Nut who is dressed in a cow suit and wants his Brown Suit back. The quest is accomplished when the player returns the Brown Suit, and the quest reward is a unique armor, the Bovine Plate. The player might also find a Gray Suit, though its sole purpose is to enhance the humor-oriented nature of the quest.

Blizzard actually did put a "secret" cow level in Diablo 2 Items, although they made no secret of it. It was merely a very large area full of monsters called 'Hell Bovines' who were cows walking upright and carrying halberds. All of their sound files were of humans saying the word 'moo'. Net lore has it that the ridiculously bad voices of the cows were those of various Blizzard employees. "The Cow King" makes an appearance as a unique Hell Bovine. However, defeating "The Cow King" will prevent that player from ever opening another portal to the Cow Level on that difficulty level.

The cow level is rarely brought up other than as a joke but is still referenced in other products. The later Blizzard game Warcraft III: Reign of Chaos introduced the Tauren, a race of anthropomorphic bulls and cows, whether intentionally spoofing the joke or not. World of Warcraft features them as a playable race, and their capital city, Thunder Bluff, is sometimes jokingly referred to by players as "the Cow Level." An item even exists named "The Cow King's Hide" (this is also the name of a set item in Diablo 2 Items, along with the Cow King's Horns and the Cow King's Hooves). On the game's loading screens, one of the tips displayed is "TIP: There is no cow level.", although this was added long after the game was released.

In addition, as an April Fool's joke in 2008, Blizzard announced a new unit for the under-development Starcraft II; the "Tauren Marine," (a play on "Terran Marine") which was a Tauren suited up as a marine, carrying an "88mm Impala Gauss Rifle" and smoking a cigar. As a caption for one of the new unit's screenshots, it is said that "There is a cow level."