The Dark Spiral Quest

Quest Summary
Quest Type	Solo/Group
XP Reward
XP Cap
Item Rewards	Shield of the Strathelar Elite Tethana Manifesto Viamontian Pennant of Loyalty
Title Reward	None
Starting location	Fort Tethana
Maps	ACMaps - The Dark Spiral
Timer	20 days
Level Restrictions	126+
Level Suggestions	150+
Introduced in	Down Twisting Paths

General

There are three sides to this quest, each offering a unique reward. Note that this quest has no actual effect on your loyalties to Silyun or Sanamar.

Fort Tethana: Give to Lieutenant Durgan in Fort Tethana for the Tethana Manifesto.
New Viamont: Give to Lieutenant Dialossa in Sanamar for the Viamontian Pennant of Loyalty.
New Aluvia: Give to Lieutenant Allandal in Plateau Village for the Shield of the Strathelar Elite.

Run north of Fort Tethana to the Tumerok Post at 12.2N 68.1W and go in, tie to the surface portal (or just go through it) so you can easily return if you die.
[OPTIONAL] - Continue north to the a large blackened battlefield and go to the north side where you'll find Lord Marsan's Log Book on the ground at 17.0N 68.1W.
The dungeon portal is on top of a smoking hill in the middle of the blackened area. Climb up the hill at 16.2N 69.0W.