Zul'Aman's return heralds the reinstatement of the rare Raptor, Tiger and Warbear mounts. Zul'Gurub was an evil troll-themed 20-man raid added to World of Warcraft in 2005 (patch 1.7), back when ...

The saving grace of both this and the tiger mount (see below) is that, rather than being on a 7-day reset, Zul'Gurub is on a 3-day reset, so you get slightly more than two shots a week at both.