Thay has become a terrible undead threat.
The former land of the Red Wizards is now under the control of a single power-mad regent: Szass Tam. He nearly succeeded in performing a ritual that would have made him an immortal being. Szass Tam failed, but in so doing he transformed Thay into a nightmare land of death. Now the regent is intent on expanding Thay’s borders so that he can attempt the ritual again.