The cutscene shows they actually manage to lure out the Lich King from inside the mountains with a Vrykul army no less, but at the same time Grand Apothecary Putress attacks the Wrath Gate. In the battle Saurfang the Younger is killed by the Frostmourne and Highlord Bolvar Fordragon dies from the plague. After this the player gets to experience THE most epic questchain in the game. Seriously.
As a Horde player, while Alexstrasza and Krasus try to control the chaos at the Wrath Gate, you are asked to take the armor Saurfang the Younger to his father in Warsong Hold. He immediately sends you to Orgrimmar where the effects of the devastating attack already show. Everywhere outside and inside the city Forsaken Refugees, martial law in the city, all services are shut down, Overlord Runthak trying to control the angry crowd of vendors.
In Thrall's Chambers Zul'jin is missing but Sylvanas is on his right side at the throne. As Thrall debriefs you on how Varimarthas - a dreadlord, right-hand of Sylvanas - launched a surprise attack on The Undercity Lady Jaina Proudmoore teleports herself in bringing terrible news. The King of Stormwind is about to declare war on the Horde for Bolvar's death. Thrall reveals to her that it was not the Horde, but Varimarthas who appears to have been misleading everyone over all these years.
When arriving to The Undercity, Zul'jin awaits you, but shortly after Thrall and Sylvanas arrive too to retake the city from the Scourge. With the help of crazy buffs, the small player army, 3 heroes of the Horde and their guards slowly manage to overcome the courtyard of the city dispelling the blight being spread there and defeating a huge Grobbulus-like boss. Progression into the city is soon halted as the elevators are out of service. No worries, Thrall calls the Element of Wind to help form a cyclone easing our decent.
Below the sad new face of the city presents itself as all personell that didn't manage to escape is dead or worse (worse being reconverted to mindless Scourge now opposing us). After fighting our way through the inner city we stop again as doomguards begin the bomb us where the Auctioneers used to be and we have ourselves a huge Kazzak-like boss to defeat. Now the only thing left is cutting through the Scourge to the Royal Quarter where Varimarthas keeps opening portals to bring in more and more soldiers. Defeating him is not easy but eventually we manage - knowing that he will surely be back as dreadlords cannot be killed with any known methods.
As one of the betrayers is dealt with, our army now moves to kill Putress... or not. The King of Stormwind and his elite guards arrive with fury and the intention of destroying all of the Horde. As the two groups jump at each other Lady Jaina teleports in and freezes everyone. She teleports all of the crazy Alliance dudes back home to have time to explain everything.
Sadly it appears she has not succeeded. All out war has broken out between the Horde and the Alliance again. Thanks to the retarded King, instead of joining together to kill the Lich King, we now fight each other to make the Scourge's job a little bit easier. Thrall says "It ends like it began... All that we have fought for in this world is lost. The hopes and dreams carried by my father and mother... by Doomhammer... Gone...".
. Maar dit zal toch niet het einde zijn hoor aangezien ge in de laatste raid instance de lich king gaat slayen veronderstel ik?