Menace of the Underdark (story arc)

Web of Chaos
These are Update 13 contents. All 3 quests are required and must be completed to start your journey to the Forgotten Realms. Quest givers all located in the Harbor.
 * The Lords of Dust
 * Servants of the Overlord
 * The Spinner of Shadows

Beyond the Rift
Update 14 contents starts here. The entrance for Servants of the Overlord and The Spinner of Shadows quest now works as a town area. Bestow Beyond the Rift from Tavnar Kronnak inside. Quest entrance is also located nearby.

Eveningstar
After finishing above 4 quests, you are finally in the Forgotten Realms. Explore the town area of Eveningstar, enjoy its different flavor and pick up the following quests.
 * Menace of the Underdark: The Darkening bestowed by Adamor Thellik
 * This is a chain quest/flag quest. There's no specific adventure instance associated.
 * Impossible Demands bestowed by Helena Falagon
 * The Unquiet Graves bestowed by Barana Talmere
 * The Lost Thread bestowed by Cormul Haythorne

The King's Forest
Explore deep into the King’s Forest and defend the village of Eveningstar from Lolth’s Drow legions!

Explore the area, locate dungeon entrances of above 3 quests and complete them. Then, head back to Eveningstar, collect rewards and advance to the following quest. When it is completed, Menace of the Underdark: The Darkening flag also is completed and yields special end reward at this point. The list may contain BtCoE named items and BtC Commendations.
 * The Battle for Eveningstar bestowed by Garwyn Thane

The Underdark
Venture down into the Underdark and confront Lolth’s elite followers in the Drow city of Sschindlyryn!

...

The Demonweb
Journey to Lolth’s home plane in this Raid quest, battle demon hordes and confront the spider goddess herself as you attempt to stop her scheme!

...