Sating the Lust

Sating the Lust is a quest which requires items from the quests Neverending Nightmares and Pulling Weeds as well as a few additional items and gold pieces. The NPC is located in a fairly obscure area and the reward for completing the quest is a Potion of Blood which grants the player temporary bloodlust.

Locating the Quest NPC
The Forgotten Berserker is located under the bridge to the right of the Escalus City Center flag.

To reach it from osl head down and to the right across the brown bridge. Keep going past the flag along the path to the somewhat lower right. When you see the bridge either jump off the ledge or climb down the ladder until you are in the river. Swim down under the bridge and you should enter a new "room" containing the NPC.

Requirements
To complete the quest the player must be using a level 60 character. They must also have the following items:

20 Spider Eyes

10 Dragon Tooth

5 Black Dust (which can be gained from the Neverending Nightmares quest)

5 Demonweed (which can be gained from the Pulling Weeds quest)

The player must also have 100,000g they are willing to sacrifice.

To complete the quest head for the npc, talk to him, accept the quest, then give him the items you need. You may need to go on a few quests to get all the items or you could, hypothetically, buy the required items from a player shop (though most people are not selling them.) Once you have the items on a level 60 character with the appropriate funds, return to the NPC and complete the quest.

Rewards
The only reward for completing this quest is the Potion of Blood which temporarily increases speed and attack when used before disappearing forever.