Heaven's Fall Saviour.

"History repeats itself"— a phrase well-known to almost everyone. Naturally, these words meant nothing for a simple child but for the people of Asteros, this meant chaos.

825 years ago, there was a War. — A war so great that it almost destroyed Asteros; the world in which different races live in.
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The War sparked when the Demons of the Netherworld started to invade the Surface, which is the place where the 8 races dwells upon. The primary reason as to why the Demons invaded the Surface was to gain control upon Asteros, eventually causing the gods the descend to the surface the drive away the demons back to the Netherworld.

Even before the Great War, the conflict between the gods and the demons existed.— They were Enmities. But that time Divine Power of he gods was at its peak so the Demons stood no chance and was forced to cower in fear in the Netherworld.