The Sightless Eye

The Sightless Eye is the first chapter of Diablo II. The player starts from the Rogue Encampment near the Stash and starts the hunt for Diablo.

Act I is the introduction zone and is easy to navigate: players can follow the dirt road leading from the Rogue Encampment towards the Rogue Monastery.

Summary
The player starts off his/her journey in a quaint, makeshift Rogue Encampment within Khanduras. The encampment is populated by the survivors of the Sisterhood of the Sightless Eye, who were ousted from their Monastery by the Demon Queen Andariel. She now guards the only way east that runs through the Monastery, preventing anyone from following the Dark Wanderer. Apparently, the Dark Wanderer is seeking something in the deserts of Aranoch. Initially, the player character is not welcomed by the Sisters (also referred to as Rogues), but soon gains their trust after clearing out the Den of Evil at the behest of Akara, the High Priestess of the Order.

The player then proceeds to gain the trust of the Commander of the Rogues, Kashya, by defeating her former comrade Blood Raven, a corrupted Rogue who raises the dead to fight for Andariel in the Sisters' Burial Ground quest.

Then, the player is sent to retrieve the Last Horadrim, Deckard Cain, who is trapped by the demons who ransacked Tristram in the town itself. This quest is known as The Search for Cain. After rescuing him, he follows and advises the player throughout the game, as well as offering his insight of magical artifacts to identify any properties of the items that the player stumbles upon during his/her adventures.

In their travels, the player finds a Forgotten Tower filled with riches and defeats The Countess. The player then retrieves Charsi's Horadric Malus that she forgot to take while fleeing the Rogue Monastery.

In order to follow the Dark Wanderer's tracks, the player must brave the horrors of the fallen Monastery and face Andariel.

The first act is concluded with the defeat of Andariel, allowing the player to travel with Warriv's caravan towards the desert city of Lut Gholein.

Quest Necessity and Tips
One who wishes to give chase to the Dark Wanderer only really needs to complete the Sisters to the Slaughter quest, but the other 5 quests provide aid to the hero after completion:
 * Completing the Den of Evil rewards you with 1 Skill Point
 * Completing the Sister's Burial Grounds, if alone, provides you with a free Rogue hireling
 * Completing the Search for Cain rewards you with free Identification services from Deckard Cain, a randomized ring from Akara, and a 10% discount on most wares. The ring Akara offers is Magic quality in Normal, and Rare in Nightmare/Hell.
 * Completing the Forgotten Tower rewards you with a reasonable sum of treasure from the Countess' chest.
 * Completing the Tools of the Trade allows you a one-time Imbuement, making a Normal quality, unsocketed Item a Rare item.

Development
Monster planning sheet of Act I released by the lead artist Phil Shenk, shows that this Act originally was cold and frozen with steppes and tundras. And old monster names like Zombie - Frozen Dead, Quill Rat - Ice Rat/Ice Porcupine. There was also a plan of Giant Eagle enemies.

Trivia

 * Much time was spent perfecting Act I during the development of Diablo II, as it would likely be used in a beta test or demo. The generalities of the act were solidified in the second half of 1997; less than a year into the game's development.