Not all Targoroth dragons were large. Some of them stopped developing and remained dragons forever.

Thus, the Gastres dragon was the smallest of the brood. Members of the royal dynasty did not want to take it, so the lizard went to Gartosh Targoroth, a bastard. Because of his background, he could not hold official positions, so he became a master of spies.
In such a craft, the small dragon Gastres came into place. Together with his master, the lizard penetrated enemy castles and started arson, stole artifacts and obtained valuable information about enemies.

Is this story true? No one knows. But the dragon Gastres remains in the past of the Sphere and right now everyone can become its happy owner.