The Achilles II was an Achilles-class DropShip owned and operated until at least 3067 by the mercenary unit known as The Medusans. The Achilles II and the Kuan Ti-class Petard formed the Third Division of Hydra Assault Squadron, serving under the commanding officer of the Third Division, Captain Jonathan "Hooky" Bell.
When the Medusans attempted to defend New Syrtis from a Capellan strike force in 3069, the Achilles II was one of the ships involved in launching a deep space ambush against the Capellans. While the Medusans managed to destroy a Leopard and a Triumph and damaged a number of other Capellan DropShips, the mercenaries took damage in turn from the Capellan forces led by the Impavido class WarShip CCS Zhejiang, which was escorting the strike force. Achilles II took damage during the combat, and while the damage was repairable, the damage inflicted on shipyards throughout the Inner Sphere by the Word of Blake as the Jihad escalated meant that the Achilles II was still waiting for those repairs at the end of 3071.
- Mercenaries Supplemental II, p. 50, "Hydra Assault Squadron: Many Heads Make Light Work"
- Mercenaries Supplemental Update, p. 90, "Medusans"