There were many things in the book but it revealed clearly the Araguans' superiority complex. They called themselves the "descendants of God" while the others were "scum of the earth."
In Aragu, the elves, dwarves, and Northern Beastmen were even lower than horses. They could be sold, killed, and humiliated at will, treated like tools. Once a slave became sick, they would be killed immediately. Instead of burying the body, it would be sold to a butcher. There, it would be cooked and fed to hunting hounds, griffins, wolves, and other trained carnivorous beasts.
The encyclopedia also listed the prices of the different slave meats. Elves were the most expensive because they were the most tender. Amongst them, meat of elven girls was the most valuable. They were usually fed to the pets of nobles. Dwarves were the cheapest. Their meat was described to be rough as sandpaper. Even dogs weren't willing to eat it.
In this world, all power under the Legendary Level was known as Tier-1. Legendary Level-10 was Tier-2. Legendary Level-17 of Firuman was Tier-9 here and Magicians of that level were known as Masters. Level-18 was Saint. As for Level-19, that was almost God-like. It was the pinnacle of humanity and was known as the Archmage!
In Aragu, there was currently one Archmage, three Saints, and 18 Masters. They could easily destroy everything in the world. As for official Magicians, there were countless. An ordinary little town could produce someone like Rockman. Just imagine how many there were in the world!