The various races of Yon have always enjoyed peace (except for an uncontested goblin raid or two) until a dragon appeared.
This dragon terrorized locals and livestock until several wannabe heroes rose up from the mud (truly, for they were mud farmers), and decided to end the evil.
Gathering companions and soldiers along the way, they fought their way to the Dragon's Keep until one hero defeated the dragon, restoring peace and unmelted cheese to the land. At least, that's how the story goes... …