Blizzard has greatly increased the drop chance of some Mists of Pandaria and Warlords of Draenor mounts from world bosses on live servers via a hotfix.
(Source)
Items and Rewards
The drop chances for Son of Galleon’s Saddle, Reins of the Heavenly Onyx Cloud Serpent, Reins of the Cobalt Primordial Direhorn, Reins of the Thundering Cobalt Cloud Serpent, and Solar Spirehawk have been greatly increased.
