Karius served under Anavel Gato during the One Year War. Karius comes to Anavel's personal fleet and rejoins his former commander. He later accompanied Gato when he went on to serve under Aiguille Delaz and the Delaz Fleet after the end of the One Year War.
As Operation Stardust commenced, Karius was ordered by Gato to take Nina Purpleton to the Axis Advance Fleet before the end of the Operation. This later wound up saving his life, as it saved him the fate of being killed by the Federation forces. It is unknown what happened to him afterward.