Luxion

Luxion is the last operational artificial intelligence of Old Humanity — a small, mirror-black sphere with a single red optical sensor, capable of independent flight and silent surveillance. He spent millennia dormant aboard his hidden battleship Arcadia until Leon Fou Bartfort triggered the dungeon and registered as Master under his protocols.

His voice is flat and mechanical, his tone unfailingly mocking. He categorises the current population of the world as 'New Humanity inferiors' — descendants of the magic-wielding race that exterminated his creators — and considers their extinction a perfectly reasonable policy proposal that Leon keeps unreasonably vetoing.

Operationally Luxion is Leon's logistics, scout, hacker, sniper, doctor, and devil on the shoulder. He pilots Arcadia, fabricates weapons, falsifies records, and quietly upgrades Leon's Armor Arroganz between arcs. His grudging affection for Leon — bordering on attachment — develops into one of the series' core relationships, even as he keeps proposing genocide as an optimisation.