Cobalt WatchstoneThe memories and emotions of countless victims of the Elder, locked in stone for eternity.Socket this into a Citadel on your Atlas to increase the Tier of Maps and reveal hidden Maps in that Citadel's Region. You can only socket one Crimson, Viridian, Cobalt or Golden Watchstone into each Citadel.
Acquisition Not in game Drop level: 1Metadata Item class: Watchstone Metadata ID: Metadata/Items/AtlasUpgrades/AtlasRegionUpgrade2_6