The Forgotten

 is a task in.

Synopsis
A group of adventurers known as The Forgotten are smuggling Engwithan artifacts into Defiance Bay. The Vailian ambassador, Vicent Agosti, wants you to find out how they're doing it so he can devise a plan to discreetly put and end to it, before it causes a diplomatic incident. To do so, he has arranged with the Knights of the Crucible to detain a potential buyer, Mestre Barcozzi from the Republics, so that the Watcher can take his place and discretely learn how they are smuggling items through Defiance Bay.

Walkthrough

 * After finishing the quest At All Costs talk to Pallegina. There is no need to accept her into party.
 * Talk to Vicent Agosti in the Vailian Embassy. He wants you to pose as an artifact buyer and figure out how The Forgotten are smuggling Engwithan Artifacts.
 * Head out to Aedelwan Bridge. Once you reach the middle of the bridge, The Forgotten will show up under Orimanth Hassan's command. You can either attack them right away, or ask about their operation. Even if you attempt to do this diplomatically, their sixth member will eventually show up and let them know the real buyer is in prison, blowing your cover and forcing a fight.
 * Kill The Forgotten. There are six of them, which can be a difficult fight if you are low level. It is generally advisable to take out the 2 wizards first, as they have access to annoying crowd control and damage spells, but have low endurance and defenses. Make sure to loot them: they carry high value coins and equipment, including a unique armor, Sanguine Plate.
 * Return to Agosti in the Embassy. Regardless of how you handled the situation, he will give you the same reward.