At the start when gods needed worshipers to sustain their power, they created Elfs, Dragons and Dwarfs.
They could've created a perfect world, a world without misery and pain but if they would've done so, who would worship them ?
Dwarfs and Elfs went to war with each other for years meanwhile the Dragons just watched from the sidelines.
As the numbers of death, pain and misery increased, number of worshippers increased but so did hate and the seven deadly sins.
As the hate piled up, new creatures came to existence... The Demons. These creatures were opposite of everything that Gods stood for.
These creatures were evil but they gave both Elfs and Dwarfs something common to fight against.
But the more the war went on, the more their powers grew and at one point their powers grew so much that they ascended to God hood themselves.
That's when gods felt fear for the first time. They felt that something evil has born into the world that can wipe out the existence of their world.
