Quest: Gathering the Ingredients

Don't worry, Spirit of Wenden will not attack you, he just wants to talk. So talk to him and find out that it was him who made all the minions spawn, but he feels that he made a mistake and would like to help. He just so happens to know a way to get rid of them. All you have to do is collect many Essences from 7 different kinds of his minions. After you have collected all the kinds, make your way to Stormwynd Beacon, and burn them in the light at the top.

Two marks will be made in your map, a mark to the Stormwynd Crypt and one for the Stormwynd Tower. At the Stormwynd Crypt you will find 3 different types of Minions: The Magus', the Acolytes, and the Boneslicers. At the Beacon you will find the Deckhands, the Mariners, the Zombies, and the Zealots. Go to each locations and kill all the mobs until you have the right amount of Essences. The mobs will all be around level 19-20 2dot, and luckily for you the droprate of these essences have been greatly improved from when the quest was first released! Each time you kill a mob, you have a great chance of getting an Intact Essence.

After you have all of your essences, make your way to the top of Stormwynd Beacon. Once you enter the top room with the light in it, your quest will update, and you will automatically throw the essences into the light. Unfortunately Lord Stormwynd has been using the URT all along. This did not get rid of the minions at all, but reanimated Lord Stormwynd himself!
Quest: Somehow Fooled
Lord Stormwynd talks into your mind and tells you to go back to Twyndy Thadtran and tell her what you have done! He's sure she will send you to try to defeat him, so he is anticipating destroying you when that happens.