Purifier

The Purifiers are an ancient robotic race created by the protoss.

Design
The original Purifiers bear the same general protoss form, if not biology. They operate more efficiently when in close proximity to each other, and a Purifier's personality can be uploaded into an empty shell. They possess a data web that is similar to the Khala, though it does not possess the same emotional connectivity. Purifiers connected through this link can speak through different vessels (e.g. one Purifier can speak through another Purifier's body provided that the link is shared).

Origins
The purifiers were built under direct order of the Conclave to be an ultimate fighting force at a time when protoss scientists were making technological advancements in intelligent robotics and artificial intelligence.[5] This force would consist of replications of the greatest warriors in protoss history. The program was originally kept in shadow and unified by the belief that consciousness could be turned into data, thereby used to preserve the thought-process and decision-making ability of a formerly living being. Studies proved that the replications were often 99.3% accurate to the protoss subject the replication was patterned after. The Conclave moved to use this technology to build a force replicated from the greatest warriors in the universe. A data web was designed to give the Purifiers a synthetic equivalent of the Khala; Hierarch Artanis would later speculate that the engineers who designed the Purifiers did this in the belief that the Purifiers could never be seen as protoss without the light of the Khala.

The Conclave did not, however, treat the Purifiers with the same respect afforded to regular Templar. Instead, the Purifiers were little more than slaves in the Conclave's eyes. Eventually, the purifiers chose to rebel, killing their masters. In return, the Conclave determined that the purifiers were too dangerous and banned them. They were powered down and launched away in a command vessel, Cybros, to be reactivated only in the direst of circumstances.

The Second Program
Sometime prior to the Great War, a new Purifier Program was designed, inspired by the technology of the original attempt. This was carried out at a facility on Glacius. The personality of Praetor Fenix, who fell at Antioch during the zerg invasion of Aiur, was used as the template for the prototype of these new Purifiers. It was estimated that the replication was accurate of the original template to within the 99th percentile.

Reactivation
During the war between Amon and the Daelaam, Hierarch Artanis came to Cybros to reactivate them, though also had to deal with the presence of the zerg. After activating the Purifiers in Cybros, the Purifiers set to purify Endion through the vessel's weaponry, purging it due to massive zerg infestation. They then agreed to fight for the Daelaam after given reassurance by Hierarch Artanis that they will be treated as equals, as long as the Purifier with Fenix's consciousness became their representative. The Purifiers were present during the Daelaam's second attempt to reclaim Aiur, alongside the Tal'darim and Nerazim. When Amon's host body was exposed,Cybros, the Death Fleet, and the Spear of Adun rained heavy weapon support and destroyed his physical form. The Purifiers held the southern entrance during the final defense of the Keystone, and were commanded by Phase-smithKarax. The Purifiers and their Daelaam allies were successful in activating the Keystone and driving Amon back into the Void.

When Hierarch Artanis lead the Daelaam into the Void for a final strike against Amon, Purifier sentinels and colossi accompanied his forces.