Fervor of the Frostborn

The encounter with [npc=30142] is pretty straightforward. Just throw the [item=42624] at the giant, which will do a lot of damage and stun it. Then run away. As soon as the cooldown is up, throw it again. When the giant is low on health, the game will announce: "The Iron Watcher reels, reaching to its now useless eyes, and charges blindly." It will run to the end of the bridge, which is your cue to toss the hammer one last time. It will lose its balance and plummet to its death.

What was more interesting to me was the story [npc=30401] tells you as he flies you to the encounter:

King Stormheart is putting you to the test, eh? He must see something in you to begin with or I doubt he'd put you through such a sacred ritual.

I know you're new to our kind, so I'll catch you up a bit while we're on our way over.

Years back, my father and several other frostborn were returning from a trek across Dragonblight. There was a heavy blizzard... far worse than we've ever seen since.

They crossed a trail of blood-soaked snow and followed it to find a dwarf wandering and speaking in a dialect they couldn't make out... and not a dwarf of our kind mind you, but a mountain dwarf - something our kind had never seen before.

The dwarf seemed lost, having no memory of where he came from, or even of his own name. Not being the kind to leave a dwarven cousin to die in the snow, my father's party took him in and continued back towards Frosthold.

Not long later, out of nowhere, the snow burst before them and a jormungar the size of Veranus herself came down upon their party... one of them was swallowed whole before they even had time to react.

My father thought they were all doomed... but behind him, a furious roar rumbled across the snow, and he turned to see the mountain dwarf growing in size, his skin taking on a stone-like texture, and his hands sizzling with lightning.

The dwarf barreled forward with a sound like rolling thunder and hurled a shining metal hammer, lightning coursing over its surface, directly into the jormungar's throat.

The jormungar collapsed instantly, its head barely still attached to its convulsing body. My father turned to the dwarf in awe and raised a fist in praise...

The stranger having no name of his own, my father deemed "Yorg," a name reserved for champions of legend. Years later, he now stands before us as Yorg Stormheart, King of the Frostborn.

King Stormheart has trained us well... turned us into even more fearsome warriors than we could have boasted during the time of our war with the Frost Giants.

And as one of the fiercest tests put upon a warrior of the frostborn, we are made to face a creature far larger than ourselves--giants, dragons, jormungar--as a testament to the fact that size will never be our weakness.

This is the test put before you this day. Return to us only once The Iron Watcher is dead, and be revered as a warrior of the frostborn.

He is slow from the rust of the ages... be quick on your feet and he will not best you. You have King Stormheart's favor - do not disappoint.

If you've seen the cutscene for the quest Frostmourne Cavern, you can probably figure out Yorg's actual identity.

Tried this quest today while going for Loremaster. After speaking to the guy, the bird would appear briefly, then be gone. If this happens to you, you can complete the quest by flying yourself. You do not have to ride the white bird.

Just make sure to loot the hammer before you attack The Iron Watcher.