He wields his unique weapon, the Orator Baccus Sword. If you are fighting a war against him, putting his kingdom at its heels (6 or less castles + cities) and have him as a prisoner, he will be willing to give you his sword in exchange for his freedom, but this will reduce your relations with the king by 40 and with The Empire by 5 (note: player has to be monarch for this to happen). Rarely, he will use his other blade, a Runed Bastard Sword. Stats-wise, he is the weakest monarch.
He rides a Dark Crimson Charger. His armor (Immortal Primus Armor) and his helmet (Marius Helmet) are both unique items and the player can only obtain them capturing his home city (Janos) and checking the City Chest.
"We came to Pendor in order to spread enlightenment to a backward society. Now that Pendor is our home, we find that our ancestral lands have been corrupted. It is we who must guard against the decadence of superstition." -Marius Imperator, Emperor of the New Empire.