The Armathrwn Society is a secret society investigating the Emptiness that invades Vana'diel in Chains of Promathia. The society is involved in many of the political decisions in the Grand Duchy of Jeuno. Among the Armathrwn Society, there are members that seem to be mindless puppets of Nag'molada. They are referred to as Mammets. Mammets change their job periodically as they fight, assuming the roles of Black Mage, Dragoon, Monk, and Warrior. However, a yellow liquid secreted by their bodies is somehow capable of preventing this transformation if splashed upon them. As a result, adventurers sometimes collect the liquid from the Mammets' bodies to sell to other adventurers on the Auction House. Even after the Emptiness is thwarted, Mammets continue to invade Monarch Linn for unknown reasons. The man known as Justinius often enlists the aid of adventurers to eliminate the robed invaders, rewarding them with a random item from his massive collection.
- Mammet-19 Epsilon
- Mammet-22 Zeta
- Gravity Wheel: AoE damage and Weight. Only used when wielding a polearm.
- Microquake: Single target damage. Only used when wielding a polearm.
- Mind Wall: Absorbs all magical damage and converts it to HP. Only used when wielding a staff.
- Percussive Foin: Cone Attack damage. Only used when wielding a polearm.
- Psychomancy: AoE MP Drain. Only used when wielding a staff.
- Scission Thrust: Cone Attack damage. Only used when wielding a sword.
- Sonic Blade: AoE damage. Only used when wielding a sword.
- Transmogrification: Absorbs all physical damage and converts it to HP. Only used when unarmed.
- Tremorous Tread: AoE damage and #Final Fantasy XI|Stun.
- Velocious Blade: Five-hit single target attack. Only used when wielding a sword.