This quest can be murder. I had a lot of trouble in my green-equipped warrior. I'll try and smooth over the trouble spots.
First of all, remember that he pauses for a few seconds after each confrontation. Take that time to bandage up or even grab a bite to eat if you need it.
The first real problem comes when he goes after the second supply depot. If your not carefull he'll charge headfirst into a group of three sailors and one marksman. The marksmen are brutal: their aimshot takes a huge section of your health away and they can do that while raining both you and hanes with arrows (Despite the fact that they use guns...). What you need to do is pull one of the sailors away while hanes is still moving forward. Once he's dead pull anoether one while hanes contemplates his navel. With luck you can avoid the marksman (Who patrols across the whole encampment) altogether.
Once he burns the third depot watch out: he'll make anoether suicidal break for the gate. I don't know if this always happens, but when i was there the whole area was doused in fire and gave you a dot that does 800 damage per tick. He'll also aggro three more sailors. Lovely. Let him go in first, chances are you can't take all three of them yourself if your low on health, mana and cooldowns from the previous encoutners.