Act 3 Quest 3: Khalim's Will - Diablo 2
Quest Location: Act 3
Quest NPC: Deckard Cain/Ormus
Quest Goal: Create Khalim's Will & Destroy Compelling Orb
Reward: Khalim's body parts are no longer taking up inventory space
Flag: Can enter Durance of Hate
You can begin this quest by speaking with Cain after completing Act 3 Quest 1: The Golden Bird or when you find one of Khalim's relics, whichever happens first. This quest is a lot like Act 2 Quest 2: The Horadric Staff in the sense that it has you run around to multiple dungeons for multiple items and then combine them into one.
For this quest you need to collect Khalim's Eye, Brain, Heart and Flail then combine them all in the Horadric Cube to make Khalim's Will. You can then use this item to destroy the Compelling Orb which blocks your entry to the Durance of Hate dungeon. Completing this quest will flag you to enter the Durance of Hate and also allow you to retrieve the Waypoint.
Where to find each item:
Khalim's Eye: Spider Forest > Spider Cavern
Khalim's Brain: Flayer Jungle > Flayer Dungeon
Khalim's Heart: Kurast Bazaar or Upper Kurast > The Sewers
Khalim's Flail: Upper Kurast > Kurast Causeway > Travincal
Khalim's Eye - Spider Cavern
The Spider Cavern is found in Spider Forest which is the very first zone you come across in Act 3. Be sure not to confuse the Spider Cavern with the Arachnid Lair, another spider dungeon that typically spawns next to the Spider Forest Waypoint. Khalim's Eye will only spawn in the Spider Cavern.
Once you make it to the Spider Cavern, what you're looking for is a Golden Chest which will contain Khalim's Eye. Keep an eye on your map if you're having trouble locating the chest as it'll appear on your map when you get close enough. Each chest involved in this quest will appear on your map when you approach it.
Every Golden Chest with a Khalim quest item is marked on your map (like above).
Khalim's Brain - Flayer Dungeon
Khalim's Brain is located on level 3 of the Flayer Dungeon in a Golden Chest that can spawn in any of the four corners of this floor or in the center. This level of the Flayer Dungeon is one giant maze usually with dozens of dead ends which makes navigating it a real pain in the butt.
The Golden Chest we're looking for is typically guarded by a Super Unique Flayer Shaman by the name of Witch Doctor Endugu. Depending on your difficulty he will be fire and magic resistant or immune. He also deals heavy damage (much like all the Flayer Shaman enemies).
Khalim's Heart - The Sewers
You can find the entrance to The Sewers in either Kurast Bazaar or Upper Kurast, the zone is connected to both. This zone is extremely large and you're looking for a small little island with stairs down to Level 2 and a switch/lever that you need to hit to clear the rubble over top the stairs. The switch is always right next to the stairs, only the location of the stairs changes each time.
The Golden Chest that contains Khalim's Heart is easily found on the Sewers Level 2, typically guarded by one Champ/Boss pack.
Khalim's Flail - Travincal
Last but not least you need to defeat the High Council which is found in the Travincal for Khalim's Flail. When you approach the High Council you'll also begin the quest Act 3 Quest 5: The Blackened Temple. Both of these quests will complete at the same time, once the High Council is defeated and the Compelling Orb is destroyed.
Once you've defeated the High Council place Khalim's Brain, Heart, Eye and Flail into the Horadric Cube and hit combine to form Khalim's Will. Equip this item and use a regular melee attack on the Compelling Orb to destroy it and complete the quest as well as gain access to the Durance of Hate.