The Fall of a Hegemony
The Draconic Kingdom that was situated at the center of the Beast World was the kingdom that commanded the most power. With the mythical race of dragons at the forefront, the kingdom prospered and took the lead in erecting a stronghold that withstood the test of time for multiple millenia.
In the kingdom, there were multiple floating cities where powerful dragons resided, ruling over the masses of the common beasts below them. Their power boasted such unshakable belief, that the day they fell became the most shocking thing for the beings of the Beast World to hear.
The invasion of demons began abruptly, with multiple Demon Kings descending down in areas not too far from the Draconic Kingdom. They were somehow equipped with all the knowledge of the Beast World as they began waging war right away, causing the battalions of Black Dragons that protected the kingdom to move against them.