Magister Vlasty is researching the dark horror, an undead monster. He needs unbroken skulls for the research, and asks you to hunt dark horrors and bring the skulls back to him. Dark horrors are found in the swamps southwest of the village. Even broken skulls will fetch you some adena.
You have obtained intact skulls of dark horrors. Take them to Magister Vlasty for a reward. He also pays for broken skulls, but not as much.