Quick answer: After killing Baal on a difficulty, cube Wirt's Leg (from Wirt's body in the western corner of Tristram) with a Tome of Town Portal while standing in the Rogue Encampment — a red portal to the Secret Cow Level opens. Farm Normal for 4-socket Spirit sword bases, Nightmare for skiller grand charms, and Hell for runeword bases and high runes. Leave your Magic Find at home.

What is the Secret Cow Level?

The Moo Moo Farm is an easter-egg area populated by 350–450 Hell Bovines — the highest monster density anywhere in the game — plus the Cow King in his little fortress. Two properties make it special for farming: the density itself, and a near-total lack of immunities. Only the Cow King is naturally immune (to lightning), so virtually any build with area damage can clear the zone.

How to open the portal

  1. Kill Baal on the difficulty where you want to open the Cow Level (complete Act 5, Quest 6). Each difficulty's portal is unlocked separately.
  2. Grab Wirt's Leg: open the red portal to Tristram from the Cairn Stones in the Stony Field, fight to the western corner of the map, and loot Wirt's body.
  3. Stand in the Rogue Encampment (Act 1 town), put Wirt's Leg and a Tome of Town Portal in the Horadric Cube, and transmute. The red portal appears next to you.

One piece of legacy knowledge to unlearn: in the original Lord of Destruction, killing the Cow King locked you out of reopening the portal. In D2R it doesn't — kill him as often as you like.

What to farm on each difficulty

DifficultyMain targetsWhy
NormalCrystal Swords & Broad SwordsCow-sourced swords are the right item level for Larzuk to punch exactly 4 sockets — instant Spirit bases for leveling. See our socketing guide.
NightmareGrand charms ("skillers"), resistance & life charms, flawless gems, jewels, rings, amuletsThe best skiller-charm farm in the game, and the resistance charms smooth your transition into Hell.
HellRuneword bases (Monarchs, Berserker Axes, Threshers), charms, every rune up to ZodArea level 81 unlocks almost every sought-after base — see our runeword bases guide — and the sheer kill count makes it a top rune spot.

The Cow King's Leathers set only drops in the Cow Level (boots and armor on any difficulty, the helm on Nightmare and Hell) — a trophy more than a power item. The Cow King himself is the one target here where Magic Find pays off, as the zone's best source of unique and set drops.

Why Magic Find is the wrong stat here

Everything the Cow Level is famous for — base items, runes, charms, jewels, gems — is unaffected by Magic Find. Bases and runes don't have a quality roll for MF to touch, and charms always drop magical anyway. As our Magic Find guide explains, MF only moves the unique/set/rare/magic roll. So gear for kill speed and survivability instead: the more cows per hour, the more rolls at a Zod (a rare prize at roughly 1 in 2.5 million cows on players 1 — but every cow is a ticket).

Farming tips