You light up a torch. These creatures are said to fear fire so this will help keep them from ganging up on you. Torch in one hand, sword in the other you explore the cave while your page guards the horses outside.
You come to a nest of sleeping gnorfs. You spill torch oil all around them and then onto them. when they start stirring you toss the torch onto them and leap back. They are a burning and screaming those ultra high pitched wails. You slash and hack them as they run about in blind panic. In the end they are all dead inside they're den.
It takes you and your page three hours to find the stolen jewel. It was hidden under one of 342 piles of rocks, feces, and bones. You clean the jewel off and hide it next to your heart. You return to the wizard and hand them the treasure. The wizard is over joyed. You recovered it and fast. You legend looms larger.