World of Warcraft: Mists of Pandaria, colloquially referred to as Mists or MoP, is the fourth expansion set for the massively multiplayer online role-playing game (MMORPG) World of Warcraft, following Cataclysm. It was announced on October 21, 2011, by Chris Metzen at BlizzCon 2011,and was released on September 25, 2012.[1] As of October 14, 2014, Mists of Pandaria is included for free with the base game, similar to previous expansions.

Plot

With Deathwing's menace ended, Warchief Garrosh Hellscream seized the opportunity to strike at the Alliance and expand the Horde's territory on Kalimdor. His assault completely obliterated the human city of Theramore, causing world-wide violence between the factions to erupt anew. A destructive naval skirmish left Alliance and Horde forces washed ashore on the fog-shrouded island of Pandaria, which had appeared in the open sea, defying modern maps and charts. As both warring factions established footholds on the resource-rich continent, they made contact with the noble pandaren, one of its most prolific peoples. This ancient race worked with the Alliance and Horde in the hopes of dispersing the Sha: dark, ephemeral beings roused from beneath Pandaria by the bloody conflict.

(From Wikipedia)