Instigator

The instigator is a purifier-created variant of the stalker.

Overview
Several instigators were sealed with the bulk of the purifiers on Cybros. When Artanis came to Cybros to reactivate the purifiers, instigators took part in cleansing the platform of the zerg present.

Game Unit
The instigator only appears in "Purification" where it joins several other purifier forces in attacking the zerg as the player activates the purifiers from stasis.

Compared to the normal stalker, the instigator has identical stats, but its Blink ability functions differently. The instigator stores Blink charges every four seconds, to a maximum of three. When the instigator Blinks, it consumes a Blink charge, but Blink has no cooldown. This effectively allows the instigator to Blink multiple times in succession, and to Blink more frequently than the stalker since its charges replenish faster than the stalker's cooldown for Blink.

Trivia

 * The instigator is the only faction-specific variant of a unit that is not accessible to the player. The adept serves as the purifier faction option for ranged attackers, and the instigator does not appear in any subsequent missions to feature purifier armies after "Purification"; they instead use adepts.