Western fantasy + lord + pseudo-villain (the protagonist becomes the dungeon boss and then leads his men to invade the human continent)
This is a place called the Abyss. It is dirty and crowded, with a total of nineteen floors. Explorers and mercenaries from the outside world often visit it and use it as a place to harvest experience and loot.
On this day, they finally conquered the nineteenth floor. When they excitedly looked for the legendary Dragon Secret Treasure, they found that there was nothing here. There was a young man sitting on the cold throne, looking at them with a smile: I have been waiting for you for a long time.
