Best Served Cold

Acquisition
Best served cold is received via a letter from first enchanter Orsino after finding the 3 mages for Knight-Commander Meredith. If you sided with the Templars at the beginning of Act III, this quest will alternatively be received from Knight-Commander Meredith.

Walkthrough
After you get the quest, head to Hightown at night and head to Hightown estates.

There, a battle will automatically begin when you enter the area near to where you need to be. You'll need to defeat a group of Templars and 5-6 Mages to beat them all.

Afterwards loot the bodies to find a note that will instruct you to head to the Docks. Go there and follow the arrow to your destination. You may encounter a group of Slave Hunters, otherwise head into the Warehouse. Once there open the door and you'll encounter another cut-scene before you have to battle another group of Templars and Mages.

Next you'll encounter another cut-scene where you're off to the Ruins on the Wounded Coast. Down the road you'll find another fight, and enter a cut-scene with a friendly face. Keep following the road and you'll enter the main fight, another group of (you guessed it) Templars and Mages. Defeat them, get your rewards, and head back the way you came.

Rewards

 * Sigil of the Mage Underground
 * Protection of the Faith
 * Hood of the Champion (Mage), Helm of the Champion (Rogue) or Helm of the Champion (Warrior) - looted from Grace
 * Upgrade armor Sebastian