Wirt's Leg is an item available in Diablo II. It is the peg-leg of one of the characters Wirt, who was revealed to have been killed in the siege of Tristram, allowing players to loot his hapless corpse.
Wirt the Peg-Legged Boy was a salesboy who offered a single expensive item and was found at the top-left corner of Tristram, away from the main town in Diablo I. But the item in question was only revealed if the player could churn out 50 gold only to have a look at it. It was a rudimentary form of gambling in the early days, as the item Wirt had at the time was not always rare and/or useful.
But Wirt was not always a swindler. He was a sweet and charming boy until one day some Fallen Ones raided Tristram and abducted him and some other children. The children were brutally tortured by the sadistic Fallen, causing Wirt to have his left leg paralyzed. All of the children succumbed to the torture save for Wirt, who bravely and cunningly escaped from the clutches of his demonic captors. At least, that is one side of the story; it is also said Wirt only survived because of the actions of Griswold.
When he arrived in town, he fell unconscious in the town square. The townspeople took him to Pepin who, even with all his knowledge of the human anatomy, was only able to amputate his festering leg and replace it with a wooded peg in order to save the boy's life. When he regained consciousness, Wirt was shocked to see his leg gone and replaced by a wooden appendage. His anger was made stronger when he received word that his mother had died in grief after his disappearance and the townspeople had done nothing to save him or the other children. This grief made Wirt an outcast among his peers. He slowly got himself a name by peddling (read: smuggling) unique and powerful items to warriors who had come to cleanse the evil in the Cathedral.
Wirt's Leg is obtained when the player returns to Tristram in order to complete the Search for Cain quest. In Tristram, near the top left corner, Wirt's mangled body lies on the ground and will drop the leg along with a load of gold (a reference to the huge sums of gold he took from players of Diablo I) when clicked.
After the player has completed the game (by defeating Diablo or, if they have the expansion, Baal), Wirt's Leg can be used to open a portal to the Secret Cow Level. The player has to transmute the leg along with a Tome of Town Portal.
It is not uncommon for the player to accidentally put gems in a socketed Wirt's Leg, since it often spends a lot of time in the player's stash or in the Horadric Cube. So it is best not to stash the leg to save slots, the player can always pick it up after beating the current Difficulty.
Despite popular belief, a non-socketed Wirt's Leg can be imbued (see Tools of the Trade).
Also, Wirt's Leg cannot be used to craft runewords.
Wirt's Leg, despite being of almost no use as a weapon to any class, has a very secret and arcane use. It is the key ingredient used to create the portal to The Secret Cow Level in Diablo II.
Once the player has killed the last boss of the game (Diablo in Diablo II and Baal in Diablo II: Lord of Destruction), the player must travel to the Rogue Encampment and transmute Wirt's Leg with a Tome of Town Portal (is not required to be full). A portal will be created to the Moo Moo Farm, the in-game name of the Secret Cow Level.
- An item called Wirt's Other Leg is an item found near the end of the Blood Elf campaign in Warcraft III: The Frozen Throne after killing a butcher (another reference to Diablo, but the butcher is simply an abomination unit with vertex coloring made more red), and hints that the demons of Diablo are the same of Warcraft.
- Another game related to Blizzard, "D-Day Judgement" (which is a custom map), features Wirt's Leg and Wirt's Other Leg. They gain the user the ability to be permanently invisible.
- Another item known as Wirt's Third Leg is a rare item found in World of Warcraft.
- Diablo III also has Wirt's original leg.