Ambo Cash at the Wintergarde Mausoleum in Dragonblight wants you to find Plunderbeard.
There's been talk of a tunnel dug by Scourge that connects the embalming chambers of the mausoleum with the large crypts, now unearthed by Thel'zan and his minions. I recently sent my best rogue, Plunderbeard, in search of answers, but have yet to hear back from him. If I were a betting man I'd wager that he's a goner.
I want you to go down those steps and head straight through the embalming chamber and look for Plunderbeard. Dead or alive, he'll have answers.