The Lord of Destruction is the fifth and climactic act in Diablo II: Lord of Destruction. It is named after Baal, the Lord of Destruction, whose trail the player follows to the Barbarian lands of Ensteig.
- Malah, The town healer, will automaticly replenish life and mana when spoken to by the player. She also sells magical weapons and potions.
- Qual-Kehk, The clan's Master at Arms who commands the men fighting to protect Harrogath. He will allow you to hire his barbarians after you rescue his men.
- Deckard Cain, Following you through the protal to Harrogath, he will identify items and help through quests to the bitter end.
- Anya, Daughter of Elder Aust, she will appear in town after the player saves her from her prison in the frozen river and will let you buy, sell and gamble on her stock.
- Larzuk, The local Blacksmith, who prides himself in his ability to create the finest impliments of war. He will repair armor and weapons for a cost, as well as let the player buy and sell from his stock.
- Nihlathak, The last living elder in Harrogath, before he disappears, he will let the player gamble on his items.
After going through the portal that Tyrael opens after Diablo's defeat in the Chaos Sanctuary, the player arrives in Harrogath, the Last Bastion of Order on the slopes of Mount Arreat, in Malah's own words. Initially, no one except Malah, believed the player to be of any use in the ensuing conflict against Baal's Demonic Legions other than being cannon fodder for the Barbarians, especially the last surviving member of the doomed Council of Elders, Nihlathak.
But the player quickly proves his worth when he bests one of Baal's strongest generals, Shenk the Overseer, in combat, stopping the Siege on Harrogath. Larzuk the Blacksmith offers to socket one of the player's items as a reward, a service not normally given to anyone.
Qual-Kehk warms up to the player but still wants him to prove his worth. He sends the player out in the Arreat Plateau to rescue some of the Barbarians who have been held captive by Baal's forces. Soon, the player finds that the very fortifications that the Barbarians built to hold the demons at bay are being used against the Barbarians themselves by the Legion. The player is successful in rescuing the captive Barbarian warriors and the player earns Qual-Kehk's trust, who allows some of his warriors to aid the player in his quest. As news of the player's exploits spreads, Malah requests the player to aid her in something that was prodding her mind, the daughter of the Head of the Council of Elders, Anya had disappeared. And she feels that Nihlathak is responsible for her disappearance. The player follows Malah's clues to the Crystalline Passage, where he finds Anya trapped in a prison of ice. Anya is rescued but Nihlathak goes missing.
Anya explains Nihlathak's real plans to give Baal the Relic of the Ancients to spare Harrogath. But in doing so, Nihlathak has allowed Baal to pass through and avoid confronting the spirit guardians of the Worldstone without a challenge, and doomed the entirety of Sanctuary. Baal was to meet Nihlathak at his temple. So, the player follows him, trying to stop the traitor from dooming the world. After finding Nihlathak and defeating him, the player searches his lair for the Relic of the Ancients, but does not find it. Baal already has it and rushes towards the Summit of Mt. Arreat.
The player follows Baal and meets the Ancients, spirits of the Nephalem. They block the path of all who are unworthy. After a great fight, the Ancients are vanquished and they allow the player rightful passage to the Worldstone Chamber.
But Baal was already at the chamber waiting for the player. Taking a cue from his fallen brother, he summons his finest warriors from beneath Hell. The melee inside the Worldstone Chamber ends in Baal fleeing inside the heart of Mt. Arreat itself, where the player battles the Lord of Destruction ending the reign of the Prime Evils over Sanctuary.
- But twenty years later, has it really ended?