Samed:
Collect corpse pieces from the Ruins of Despair or the Ruins of Agony. If you don't know how to find the ruins, ask Guard Curtis or Guard Babenco. From the zombies, bring their head, heart, and liver. From the skeletons, bring the skull, spine, rib, arm bone, and thigh bone.
I also need bone pieces, but actually I need a Complete Skeleton of Human form more. Unfortunately, when you fight with the undead, their body shatters so it will be impossible to find a Complete Skeleton. But the person that took this job before you found one somehow.
Ah, and don't bring back anything from the spartoi. Spartoi are his minions... It is better not to make him angry.