Purifiers: Templar-Caste Protoss memories digitized and stored on mechanical Protoss-shaped forms designed to fight. Conclave built them, treated them like slaves (unlike their memories mentioned). Purifiers rebelled due to it, and then were shut down. Recently, they were woken up. They deal with Zerg like Zerg were just 'another day at the office', and could probably just overwhelm everywhere if given resources and many production facilities. ...From personal experience. Furthermore, I did not expect to encounter [Fenix, again!?] as a Purifier.