I've been all thru Marten's Bluff, upper and lower. I've taken care of the T'Rang. I found the words, but I cannot find the idol. I thought it was in the sea caves, but apparently I was wrong. Could someone please point me in the right direction?

In upper Martens Bluff (MB) behind the room with the rapax trap is a big door which is opened (i am not sure here, could have been another lever) by the lever in the inner part of upper MB(accessible by stairs from lower MB) just before that four-faced arrow-trap. Behind this big door is the entrance to a small tower where you find some items in the right part and the idol in the left part.

I had totally forgotten about that big door to the south. Duh...