Best Protoss Characters in Starcraft

Zeratul is a Dark Templar who personally slew the cerebrate Zasz, but in turn accidentally gave the Overmind the location of Aiur and was manipulated by the Queen of Blades during the Brood War into killing the Second Overmind and Raszagal, the Dark Templar Matriarch.
These events, and the discovery of the hybrids, led Zeratul to go into seclusion to contemplate his actions and investigate. As the Second Great War approached he began to take a more active role once again.

Artanis is a young protoss and member of the Templar Caste. He was appointed executor to replace Tassadar. At only 262 years old, he was young to achieve such a high rank. He later achieved the rank of hierarch following the Brood War, with Executor Selendis being his chief direct subordinate.

Protoss high templar and executor in charge of the expeditionary force which made first contact with the zerg. His forces also made first contact with the terrans when they sterilized the surface of Chau Sara in an effort to stem the growth of the zerg. Tassadar was extremely reluctant to sacrifice the terrans in order to destroy the zerg. He eventually lost his position as executor for sparing the terrans.