Sheevra Chieftain  

Go across the stepping stone bridge south of Howth (or swim
across) and go into the valley behind the mushroom ring. Hug the left wall,
and take the first left, going past walking rocks. (I wouldn't recommend
going directly over the mountains as there are many red-purple aggressives
in this area.) Veer to the right when the valley opens up, and a large camp
of sheevras will be in front of you. Chieftain spawns inside there