According to Zaeed Massani, Garkko is a "mean son of a bitch." Garkko was formerly a drill sergeant on Palaven, but more trainees died rather than graduated under his tutelage. The Turian Hierarchy sent him to C-Sec, but the Citadel organization promptly sent him back after more incidents of brutality.
While walking down the frigate's corridors with his men Garkko notices something amiss in fellow shipmate Commander Polonis. He furtively follows and catches Polonis attempting to open an airlock. Garkko has his men subdue the treasonous turian and becomes aware of a mercenary plot to board the Verrikan. The mercenaries are on the other side of the airlock, which Garkko's team promptly vents open to space. Three out of the four would-be boarders survive, prompting Garkko to question Polonis. When no answers are forthcoming, Garkko orders his men to search for the hostiles in case they breach the ship, wanting them captured alive for personal interrogation.
Garkko and a small detachment run across Zaeed during a sweep of the ship. His soldiers are annihilated by an explosion, leaving him to be captured by Zaeed. Garkko warns Zaeed he'd better kill him, and the mercenary assures him it's high on his to-do list.
The security chief is dragged at gunpoint by Zaeed to the bridge door, wanting to use him to override the security protocols. Garkko threatens to feed Zaeed his own heart, but the merc just dares him to find it first. The bridge door opens, revealing over a dozen armed turians with weapons aimed at Zaeed. Garkko smugly claims victory, but his head explodes in a shower of blue before Zaeed could reply. One of the other mercs arrived and shot him from behind.