The Raging Dwarf

Walkthrough
Talk to Jorge the dwarf near the minecarts. He says that he has had enough of a dwarf named Marvin, they say he's been kidnapping other workers here and wants you to check it out. Accept then go down the rope to the living rock caverns and mine some concentrated coal, there should be a piece of ragged cloth, examine it then leave that area. Go back to the minecarts and give Jorge the rag, he will say it belongs to a worker called biff and he mysteriously went missing a few days ago.

Talk to Marvin whom is found near the rope of the rock cavern's, he will shout at you and one of his friends will attack you. Kill him and then Marvin will storm off to a cavern and then mine the walls to cave in. Push the rock to make a small hole and fit through it, now you will reach a dead end, cast Crumble Undead on the wall (need 81 so it is powerful enough to break it).

You will then be attacked by a dwarf scout, kill him and take his objective note, it will say a list of kidnappings, now you will need to go back and talk to Jorge because on the note it says Adventurer (level 138). He will tell you that Marvin used to be a very strong warrior himself and when he challenged the selvig beast (level 7800) he lost, so he then got angry and started going crazy.

Now go back into the cavern and be prepared to defeat a level 520 dwarven warrior (very very hard), enter and a cutscene will occur of him and a Dragonite pickaxe, and a magic cape (t), he will tell you that if you do not leave he will kill you. Fight him, he will use magic and melee, avoid his magic rock throwing attacks, can deal up to 790 damage. When you defeated him report back to Jorge for your reward.

Rewards

 * Dragonite pickaxe
 * 5,000 iron ore
 * Access to the secret Dwarven mine
 * If you speak to the Dwarf leader after the quest, he will give you 40,000 exp in four skills and he will say he found a zeal ticket worth 20 zeal (find them while mining in the mine also).