Skul The Hero Slayer Key

The human race attacking the demon king's castle is nothing new and has happened countless times.

What makes it different this time, however, is that the Adventurers have decided to join forces with the Imperial Army and the "Hero of Caerleon" to lead a total attack in the hope of eliminating the Demons once and for all. .

They attacked the Demon Fortress with an overwhelming number of people and managed to completely destroy it.
All the Demons in the castle were taken prisoner, except for a lone skeleton called "Skul".