Achilles Plutarch is the Gear Vendor of Nexus Tower. Achilles Plutarch's booth is located in the Sentinel War Room, near the Sentinel Combat Challenge. There, he sells numerous items, including several two-handed weapons. However, his items come with very high price tags. Players are eventually sent by Olivia Nightshade to return the shield to Achilles Plutarch. The Spartan explains to players that he no longer has the Thinking Hat they seek. However, he hands over Ace Warprider's jetpack, requesting that players return it to the astronaut.