From Guild Wars 2 Wiki
This strongbox is visible from the Faren's Flyer Waypoint. To reach it, climb the ramp to the top of the outpost, and then glide northwest from the Wreck of the Thunderbreaker down to the strongbox.
- Verdant Brink: "Thunderbreaker" Strongbox — Search in the Noble Ledges area for the strongbox from the "Thunderbreaker." (2)