Present Sevren's Orders to Bethor Iceshard in the Undercity.
Bethor Iceshard, a high-ranking and powerful mage in the Undercity to the south, commands me to send him an agent with proven worth against the Scourge. You, [player], will be that agent.
Present these orders to Bethor. He will then instruct you on your mission. I don't know its details, but it deals with recruiting a wayward Lich. And it will be dangerous.
So ready yourself, [class]. You must not fail.
You may find Bethor in the Magic Quarter of the Undercity.