Dragon's Liver
Go to the Great Sand Sea. In the Searing Cove, there will be a Spiritlord and Manticore (Nass). In the Searing Cauldron there will be just Manticore again, and you will find the dragon between the first and second spike northeast from the direction you entered. Save the game first, fight, and split him. If you do not get the liver, reload the game and repeat.