Argona, a Human male, held the rank of captain and was in command of the Imperial Remnant's Starfleet. Specifically, he captained the Star Destroyer known as the Ironhand, approximately fifteen years after the pivotal Battle of Endor.
Argona was selected as one of the four officers from the Braxant Sector Fleet to have their Star Destroyers serve Flim, a charlatan impersonating the resurrected Grand Admiral Thrawn. This was part of a scheme orchestrated by Moff Vilim Disra and Royal Guardsman Grodin Tierce to plunge the New Republic into internal conflict, exploiting the controversy surrounding the publicly revealed Caamas Document. To ensure Argona's and his fellow captains' belief in Flim's identity—Nalgol of the Tyrannic, Trazzen of the Obliterator, and Dorja of the Relentless—Disra arranged a personal meeting between the four captains and the supposed Thrawn. Ultimately, the Tyrannic, Obliterator, and Ironhand were chosen to spearhead an attack on Bothawui, the Bothan homeworld; however, this assault was unsuccessful, forcing the Star Destroyers to retreat.