Amulet of the Seas
Olbross Rainmace tells you that the Jewel of the Seas you previously collected is only half of the Amulet of the Seas, a required artifact if you wish to lay Thundermace's Spirit to rest. The other half of the amulet is the Golden Tie now in the possession of the undead Prime Officer that is haunting the small village to the east.
After retreiving the Golden Tie, Olbross can assemble the Amulet of the Seas. He asks you to speak with him again when you are ready to meet Thundermace.
Tasks
1. Get 1 Golden tie from Prime Officer
2. There is only one Prime Officer in the ruins, so you may have to look for him or wait a moment for him to spawn. Give Golden tie to Olbross Rainmace (Thundermace's Ruins: 350, 983)