At the end of the first part of The Hak'u secondary quest, Hesla strongly suggested striking at the Hak'u, but Tanzi told of being freed by Hrawn and that he was hiding in a cave in The Southern Greilyn Jungle. Her mother told Tanzi to go get some rest and didn't believe her. Her mother then told your group to go there and kill them all, while your active character said that the truth would be found out. Have your active character agree to do so, to initiate this quest.

Teleport to the Eastern Greilyn Jungle, then head north along the path until it forks. Follow the path toward The Dryad Exile Colony. Walk through the colony continuing west off of the path until your group reaches an Incantation Shrine, then turn south through the stone arch and into A Small Cave. You'll note a star on the compass mini-map as your party approaches the back of the cave. Approach Hrawn the Hak'u, who says you are the one from the cave and he will not hurt you. Not all Hak'u are bad and hurt the tree ladies. Hrawn tells your group that his father is high priest, but had to go into hiding when the nasty usurper high priest took over and joined with the Morden. Hrawn asks them to help his father and he will give them gold. Agree to help and the father appears. He tells them that the usurper is hiding in an area west of the elven shrine. If you've visited that area before now, you found that your party was barred from entry there. Alternatively your party can dispatch Hrawn and his father. They'll still receive the quest reward, after reporting back to Hesla in the Eirulan infirmary, however they will not receive the additional skill point for each party member (per Hassat Hunter).

Cast a Teleport Spell to return to Eirulan. Now teleport to the Western Greilyn Jungle and head wast off of the path into the jungle. Continue to the southwest and you'll see a star on your compass mini-map. Head toward it until your party is stopped by a door. Left click on the door to be asked "Who there? Go away!" by the Hak'u Usurper. Your active character answers that she has a message from the Hak'u High Priest and says open the door! The Hak'u Usurper says he has a message for the High Priest as well and the door opens and the Hak'u attack. In Mercenary Mode, the Usurper has 3,396 Hit Points, but the Hak'u Rebel Guard minions only around 50 - 110. In Veteran Mode, the Usurper has 32,161 Hit Points, and the Hak'u Rebel Guard minions around 800 - 1,700. Take the lesser enemies out first, then finish off the Hak'u Usurper Priest. They'll receive the Hak'u Headress and other assorted goodies for defeating the Hak'u Usurper Priest and complete the second stage of the quest.

Teleport back to Eirulan and return to the Small Cave entrance using the still active Field Teleporter, if available, else use the method detailed in the second paragraph above. Enter the cave and speak with Hrawn's father, the Hak'u high priest, to receive your reward. Exit the cave and teleport back to Eirulan. Head south from the Eirulan teleporter to the tramway for the Great Hall, Infirmary. Get on the tram and take it across to the next tram, then take it across to the Great Hall. Head north towards the Infirmary, where you can see a star on the Compass mini-map, which indicates their intended destination. Enter the Infirmary and you can see Hesla lying on a cot with an orange question mark icon above her head. Go speak to her to explain that the Hak'u headdress, which was brought back, belonged to the usurper, not the high priest she and Morain suspected. Hesla admits that she was wrong and that Tanzi's story was mostly (although it was entirely) true and offers a reward of one skill point for each party member, plus considerable treasure and some gold, completing this quest.