When the deposed king of the Diamond Dogs is brought before the court of Celestia, the story he tells is far too much to believe. For if it is true, the Equestrians' conquest of his nation has been a terrible mistake.
Some ponies think Diamond Dogs hoard gemstones for the same reasons ponies do. Others think they eat them, like dragons. If ponies knew the truth, they might not be so eager to rob them of their subterranean treasure. If only they knew.