Looking for Diablo’s Cow Level? looks like this is it and oh my god what a level it is. Whimsyshire is a Secret Level, or secret land, in Blizzard’s Diablo 3. When you enter the Secret Level of Whimsyshire, a Feat of Strength along with a Banner and Sigil are unlocked. You can run through Whimsyshire level as many times as you want and you will get the In The Land Of Killer Unicorns Achievement for finding it.
Whimsyshire is level of rainbows and unicorns that may be a reference to complaints about the colorful graphics of Diablo 3. It also may be a reference to the Diablo 2 “Cow Level.”
Diablo 3’s Whimsyshire Video
You must create a Staff of Herding to find Whimsyshire. Staff costs 200K
Items needed for the Staff of Herding:
Black Mushroom – This spawns in Cathedral Level 1, Act 1
Shinbone – Spawns randomly in the fireplace in Leoric’s Manor, Act 1
Liquid Rainbow – Spawns in the Mysterious Cave in the Mysterious Chest in the Oasis, Act 2. Save the old man and he will open the chest.
Wirts Bell is sold by a merchants in the city, Act 2.
Gibbering Gemstone – A random drop from Chiltara in the Caverns of Frost, Act 3. It’s in the Ballistae fight area. If you get Ice Caverns exit out try again. The mob is random.
The Plans for the Staff of Herding drops randomly from Izual, Act 4.