Cruel Gladiator Elite Plate Armor and Lich Lord Plate!
Mists of Pandaria Gold Transmogs for Both Death and the Warlords of Draenor weapon transmogs- Shifting Felblade, Elemental Crescent, Equus, Flamegrinder, Greatsword of the Infernoand Cloudsong Glaive. Tons of other transmogs as well – full list here:
Hunter has Living Longbow from Warlords of Draenor Challenge Mode Weapon Transmogs as well!
Ensorcelled Everwyrm, Corrupted Fire Hawk, Proto-Drakes, Meta Raid Mount Reward mounts, Soaring Skyterror, Coalfist Gronnling.