[11] Vejrek:

Bring Vejrek's Head to Muren Stormpike in Ironforge.

Muren Stormpike: If you want to rise in the ranks of the warriors, then you better be tough. I can teach you new moves but before that, prove to me you can handle yourself against real foes.

Vejrek is the toughest troll you'll find in these parts, and he's who you have to beat. He has a hut in the foothills just south of Frostmane Hold

Bring me Vejrek's head and I'll know you have mettle.

Muren Stormpike: Have you been to Vejrek's hut, Duergar? Is that troll stink I smell on you?

Muren Stormpike: Vejrek sure was an ugly one, eh? Nicely done, Duergar! You have what it takes, now let's start your lesson...

You may not know it, but a strong defense is very important to a warrior. It keeps him standing against foes that'd fell others, and that's what your allies need.