The Tombstone is a particularly hot-blooded, four-armed gargoyle who seeks to become the strongest being in existence. They figure that as they are made of the same material as Eberron herself, they too can become as strong as Eberron. They train for this destiny by traversing Khyber demiplanes and fighting the denizens within, conquering Khyber in the same way that Eberron did.
They aim to one day encounter Khyber herself, and then punch her in the face.