Eliminate Lord Shalzaru, and then bring the Mysterious Relic he uncovered to Latronicus Moonspear in Feathermoon Stronghold.
[player], new scouting reports have given us a good idea on the naga chain of command. Royalty is present amongst their rank and file, and they're the ones calling all the shots.
Specifically, we've identified one of the crueler royals as Lord Shalzaru. Scouts report that he himself has uncovered an odd relic during a recent naga excavation in a cave south of the main ruins, across the water on the Isle of Dread.
Put a stop to it by putting a stop to him, and bring me his relic so we can study it.