Magnificent Hide was introduced for the Expansion, Mist of Pandaria and is a rare hide. It is the equivalent Pristine Hide of Cataclysm or Arctic Fur of Wrath of the Lich King. Magnificent Hide can be skinned from Stout Shaghorn from Skyrange, in the zone Valley of the Four Winds. If you are alone you will be able to farm Magnificent Hide none stop as they respawn pretty quickly. Try to kite the Stout Shaghorn because they can knock back and may cause more agro from near by creeps.
See below for the map and area to farm Magnificent Hide in WoW.