A Chagrian of the male persuasion, known as Grevin, existed during the times of conflict known as the Cold War and the Galactic War. These wars saw the Galactic Republic in conflict with the resurgent Sith Empire. In the year 3638 BBY, he held the rank of Vice-Commandant within the InterStellar Regulators stationed on the planet Makeb.
During the Hutt Cartel's takeover of Makeb, Grevin was in command. He made the conscious decision to align himself with the Hutts, as he believed they could provide more for him and his soldiers than the inhabitants of Makeb ever could. However, his plans were complicated by the arrival of a Republic strike team. This team, comprised of heroes from the ongoing war against the Sith Empire, arrived to support the people of Makeb. After the Republic forces successfully seized "the Ark," a large vessel intended to evacuate the Hutt leadership and their followers from Makeb before its destruction, Grevin deployed his forces to either retake the ship or to threaten the Avesta Plantation, which served as the Republic's operational headquarters and those allied with them on Makeb.
Ultimately, following the defeat of a droid assault on the Avesta estate, the Republic strike team infiltrated the Storm Carrier, the mobile command base of the Regulators, and initiated a reactor overload sequence. Grevin attempted to motivate his troops with promises of substantial rewards – one million credits for locating the strike team and ten million for their elimination – but his efforts proved futile. Grevin and his guards were killed in the reactor control room. The Republic strike force successfully escaped the Storm Carrier before it crashed into a nearby mesa and exploded.