The Regent Diamond

Origin
This gemstone was stolen from India by a slave and hidden within a leg wound. Intending to sell t, the slave boarded a ship, only to be killed by the captain who had heard word of the valuable cargo.

Effects
When touched by someone, a large open wound will appear on a random location of the victim's body, and will hide itself inside. However, despite how well it is hidden those around the user will be overcome with the desire to murder for greed over the diamond.