Complex sentence: Magic can also require various sacrifices or the use of certain materials, such as gemstones, blood, or a live sacrifice; even if the magician has no scruples, obtaining the material may be difficult.
Split into simpler sentences: Magic can also require various sacrifices or the use of certain materials, such as gemstones, blood, or a live sacrifice. Even if the magician lacks scruples, obtaining the material may be difficult.