Kalaxo was a human male who served as an officer of the Galactic Empire during the Galactic Civil War. During the events of Operation Starlight, Kalaxo held the rank of admiral and was the commanding officer of the ISD Ultima II, participating in a battle against the Alliance to Restore the Republic's Eleventh Division. As the battle continued, the Rebel Alliance's Starlight Squadron arrived, causing Lieutenant Bonnard to alert Kalaxo of the seven incoming X-wing starfighters. He inquired to if there were capital ships, to which Bonnard confirmed that there were only the starfighters. Bonnard suggested alerting Commander Ellian Zahra of the development, as she thought they might be the same squadron that Zahra recently fought against, but Kalaxo said that there was no need. The Ultima II was eventually completely destroyed by Starlight Squadron when the pilots fired proton torpedoes into a volcano that the Ultima II was positioned over, killing Kalaxo and everyone aboard.
Unlike other Imperial officers, Admiral Kalaxo wore a large fur-lined coat. He was killed during the battle.