Patch 5.4.0: Siege of Orgrimmar is a raid patch of World of Warcraft: Mists of Pandaria and focuses on the Siege of Orgrimmar from the leaders of the Alliance and the Horde to topple the ruthless warchief, Garrosh Hellscream. The patch includes a new raid, the Siege of Orgrimmar, a new area, the Timeless Isle, and much more. It also features the debut of the Proving Grounds, the Flexible Raid difficulty, and the Connected Realms feature. As another Mists of Pandaria content patch would delay World of Warcraft: Warlords of Draenor, 5.4 is the last content patch of the expansion.
Orgrimmar, heart of orcish civilization on Azeroth, was set ablaze by revolution. When Warchief Garrosh Hellscream revived the heart of the Old God Y’shaarj to empower his army, he desecrated Pandaria’s sacred Vale of Eternal Blossoms. This affront, alongside Garrosh’s increasingly dangerous conquests, led Horde rebels and Alliance stalwarts to assail the great walls of Orgrimmar, hoping to dethrone the tyrant before he ravaged an entire world. Alongside Thrall, champions of the Horde and Alliance fought their way to the Warchief’s lair beneath the city, where the battle grew so desperate that Garrosh absorbed the energies of the Old God to halt his downfall. It was not enough. At the behest of King Varian Wrynn, a defeated Garrosh was brought to trial before the August Celestials of Pandaria – but the scars of his rule will bleed for some time.