You need to find a crystal skull to be able to summon a necromancer's creature. Level 10 might be a little early to get there, though (don't recall the level of the undead that have it). If you follow the river west and a little south of the lake, it is to the south. North of that river branch is the fortune teller and a bunch of Black Ring members that I took out at level 12, but had difficulty with if there were more than 2 or 3 at a time. If you avoid that section of land you should be able to reach the mine going through lower level goblins, or possibly by swimming. The undead in the mine were much easier than the black ring members, but I think taking out the last black ring members may have been enough to bring me up another level.
While it would help to get the creature, try exploring in different directions to find easier opponents. Clear out the derelict tunnel if you have not done so already, etc (the bandit there has a fairly nice ring; I delayed turning in the quest quite awhile so I could wear it until I found a replacement).
