Muradin Bronzebeard

Role in Warcraft 3

When Arthas Menethil travels to the icy lands of Northrend in pursuit of Mal'Ganis, he finds Muradin there by accident, who mistakes Arthas as the undead at first. Arthas decides to aid Muradin in his fight against the undead, after which he discovers Muradin was on a quest to obtain Frostmourne, a legendary runeblade.
 
When the forces of Mal'Ganis began to close in on them, Arthas asks Muradin to show him where Frostmourne is, in an attempt to turn the battle. After defeating the revenants which guarded the blade, Muradin realized the blade was cursed after reading the inscription on the dais, which reads:
 
 "Whomsoever takes up this blade shall wield power eternal. Just as the blade rends flesh, so must power scar the spirit."
 
However, Arthas declares that he would gladly bear any curse to save his homeland. After which, the ice encasing the sword shattered and exploded outward, a shard striking Muradin and showing him to be killed.
 

World Of Warcraft: Wrath of the Lich King

It is revealed in World Of Warcraft: Wrath of the Lich King that Yorg Stormheart is in fact Muradin Bronzebeard and that he was merely wounded and lost his memory at the time, making him willing to take on the persona of Yorg Stormheart after being found by Frostborn dwarves shortly after his injury took place.
 
After becoming King of the Frostborn and bringing them into the Alliance, Muradin is reunited with Brann and Magni Bronzebeard in a long quest chain and after recalls his memories. He then leaves the Frostborn and sets off to help the fight against the Lich King where after he can be found inside Icecrown Citadel by Alliance players commanding the Skybreaker Gunship as well as standing next to Tirion Fordring at Lights Hammer.