A Bit of a Bind

Objectives
Slay Binder Sa'thress.
 * slain
 * Songstone

Description
The naga sorceress leading this excursion seems to be in the process of binding a larger elemental. If she succeeds, we will no doubt lose our foothold here.

Strike out at her, perhaps you can catch her off guard and interrupt the ritual. Remove the head from these snakes.

("Binder Sa'thress: The leader of the attack on the village. She seems to be a powerful mage.")

Rewards
You will also receive:
 * 16,450 XP
 * +75 reputation with Storm's Wake
 * +75 reputation with Storm's Wake

Progress
Is the seawitch dead?

Completion
I have no idea what this might be, but I don't like the looks of it.