Atherton's domain could be said as an all-rounded domain that strived to give the best protection and power for the people inside the domain.
The domain wasn't that aggressive, unlike the Queen's Judgment Day, but it was only kind and merciful to its own people.
For the light creatures that despised darkness or couldn't live in the dark with no sunlight, the Reign of Darkness was their silent burial.
The darkness in this place was not a simple dark state with no light but the darkness was fused with the aura of death.
There was no race more suitable other than the immortal blood clan to live in this deadly place.
If other races entered the domain, even if they were from the dark camp, one couldn't be sure whether they would still be wounded to some extent or not.
Not to mention those from the light camp!