Each of the Wrath starting zones offers a dungeon that players usually take advantage of in order to improve some gear slots. The items that drop off of bosses are far superior to quest rewards, so each player will usually play these once, if not multiple times. First up is the Utgarde Keep instance in the Howling Fjord.
This takes players into the stronghold of the Vyrkul to strike back for their attacks on Valgarde. Here, you will find the massive forge that is used to craft the large vrykul spears....
as well as the pens that house the fire-breathing drakes that the giants are breaking in order to become mounts.
The final boss is Ingvar the Plunderer, who is overseeing the vyrkul attacks on Valgarde. He isn't terribly difficult, but his fight has a twist. After you kill him, he is resurrected by a val'kyr, who drags him back to life in order to fulfill his task for Arthas. Once again, he is unsuccessful.
Up next is Borean Tundra's Nexus, located in the Coldarra section of the zone, near where you royally screwed up in pissing Malygos off. You head in to investigate the blue dragonflight's activities, along with some massive magical aberrations going off the charts.
Being in Coldarra, the entire dungeon is made of ice, and you'll encounter some Blue Dragonflight, their human subjects, and some magical beasties made of pure energy that have come through a rift in the magical barrier inside.
As further salt in the wound for your colossal screw-up, you actually need to kill Keristraza to complete the boss, as Malygos has completely corrupted her, forcing her to fight against you. Enjoy the item upgrades that you get from murdering someone who was trying to help you out earlier!