The Siege of Fort Ilkard - NWN Side Quest (Chapter 3)
The Siege of Fort Ilkard is a side quest that begins by speaking with Commander Damas inside of Damas' Lodge in Fort Ilkard. You can find Fort Ilkard by going south out of the Beorunna's Well town. For the first part of this side quest you'll be tasked with destroying all of the Catapults and Ballista that you find around Fort Ilkard.
In order to destroy these machines you'll need to first eliminate the Catapult Commanders that guard them. Once you've taken out the guards you'll be able to simply click on the Catapult or the Ballista to destroy it. All of the Catapults and Ballista's that we need to destroy can be found on the ground-level near the river surrounding the fort. Don't go up to the plateau yet as that's for the next part of the quest.
Once you've destroyed all of the Catapults and Ballista's return to Damas and speak with him to get your first reward and update your quest.
The next step of this quest involves going up to the plateau area above the Catapults and defeating Subchief Arness. If you're having trouble finding where Subchief Arness is then open your map and look for the Uthgardt Command Post map marker to the north of Fort Ilkard. Subchief Arness is found in this area ontop of the small platform here.
With Arness defeated make sure to loot Arness's Head and return it to Commander Damas inside of Fort Ilkard to complete this part of the quest. For the final part of this quest Commander Damas asks you to visit the Elk Tribe Keep and defeat their leader, Zokan Thunderer. You'll need to eliminate him and loot his head to return to Commander Damas to complete this quest.
Important: Technically you have 2 ways of completing this quest. If you first meet Uncas, the Elk Tribe prisoner, inside of the nearby cave you'll be given the Feather of Peace item which will allow you to enter the Elk Tribe Keep without bloodshed. This will allow you to speak with Zokan and learn about why they are attacking Fort Ilkard and allow you an alternative outcome to this quest. For more information about Uncas and how to enter the Elk Tribe Keep peacefully check out the Investigate the Elk Tribe walkthrough.
If you choose to attack Zokan all you need to do is loot Zokan's Head and then return it to Commander Damas to complete this quest. This route will get you the best reward for this quest. However, if you take the peaceful route and talk with Zokan about what ails his people he'll ask you for help. Commander Damas is the one responsible for spreading the Wailing Death in the Elk Tribe Keep as he gave Zokan infected blankets.
So, Zokan asks you to retrieve the cure from Commander Damas so that he can save his people. You'll have 2 methods of retrieving this cure from Commander Damas, you can give him some gold for it or you can attack him and loot it off his corpse. It's worth noting that if you attack him you'll turn the entire Fort Ilkard hostile to you which you may not want to do.
When you return to Zokan and give him the cure this quest will "fail" and be removed from your quest log. You're not able to give Zokan the cure then kill him for his head to return to Commander Damas.