This guy's alive?

[Rottingham]

So I've never done ICC... and I walk in while my brother is doing it. Who do I see? Muradin Bronzebeard!?

I read the Rise of the Lich King Book, and Muradin dies in it. He becomes impaled by ice I belive. Could someone show me the lore or tell the the story of how he came back to life please?

[Nia]

From WoWwiki

"In World of Warcraft: Wrath of the Lich King, in a quest in the Frostmourne Cavern in the Dragonblight, players can see a flashback of the interaction between Arthas and Muradin prior to Arthas claiming Frostmourne. It turns out that Muradin was not slain when the ice encasing Frostmourne shattered, but was merely wounded. A short time after Arthas left, Muradin awoke. Confused, hurt, and with total amnesia, he wandered out into the snow.

Muradin was eventually tracked down by a group of Frostborn dwarves, who followed his trail of blood-soaked snow during an extremely harsh blizzard. These Frostborn just happened to be on their way home to Frosthold from a trek across the Dragonblight. Not about to let their new-found cousin freeze to death, they took him along with them, and a short time later they came under attack by a jormungar. After slaying the worm single-handedly and saving the dwarves, they took him in and gave him the name Yorg Stormheart, after a legendary Frostborn warrior. Eventually, Muradin/Yorg became King of the Frostborn and brings his people into the Alliance, which had begun journeying into Northrend to do battle with the Lich King, the renegade blue dragonflight, and the iron dwarves. Despite his people befriending the Alliance and the Explorers' Guild, he expressed concern over involving his people in wars that would result in their deaths.
Reunited

After a long Alliance quest chain, Muradin is reunited with both Brann and Magni, and recalls his lost memories. He then leaves the frost dwarves to hunt down Arthas. The game then phases, causing Muradin to be replaced by Velog Icebellow.
Icecrown Citadel

Muradin commands the gunship Skybreaker during the Gunship Battle in Icecrown Citadel.[3] Alliance players can also find him standing near Tirion Fordring inside Icecrown Citadel at Light's Hammer.

If a raid member brings [Arthas' Training Sword] to Muradin, who stands in Light's Hammer, regardless of faction after the Lich King is defeated, he wishes he was able to stop Arthas from claiming "that accursed blade."

Yep.

[Epicfail]

The lore of this game is at the total mercy of the psychotic perversions of the writing staff. Instead of getting upset at lawlore, I instead applied to work for Blizzard's staff. I didn't make the cut. I guess I wasn't demented enough Gotta work on that...