Graves for Grave Robbers

Could you help me out, traveller? I'm the caretaker of this graveyard. Many of our greatest warriors rest here... At least, they used to rest. Dark Bogles've taken to robbing graves for heirlooms and treasures. I'm not strong enough to drive them away, could you help? If you kill 7 of these grave robbers and bring me their picks and shovels, I'll reward you.