*The details in this part are from the Elsword Comic Book. Which actually should have similar setting than the game but a different story. Still, I’m including this section because of that one line Karis says at the end of Sander story quest mentioning “Revenge against angels/heaven”. Which might hint that they are using this same setting.*
Once upon a time there were was a Continent.
Gods created Elves, Humans, Spirits, Monsters and many other living creatures and made them live in the Continent.
At the same time, gods drove off the Demons that had taken over the continent back to the demon realm.
However, demons didn’t like this and they organized under a Demon King named Krom. Krom and his 13 demon generals launched a counter attack against the gods and the Continent became a battleground for the Gods vs Demon war.
This war pretty much ruined the Continent and left it virtually uninhabitable for life.
The Three Goddesses that cared deeply about the living creatures in the Continent created a Giant Gem that radiated life energy. This gem was to be placed at the center of the Continent once the war was over to make it habitable for life again.
The war ended with the sacrifice of the Three Goddesses which resulted in the death of Krom.
But Krom was not truly killed. He left an embryo of his son(Angkor) back at the demon realm. This embryo, once awakened could be used for Krom to resurrect himself. Demons retreated back to the demon realm biding for the day when their king awakened again.
Elves were creatures living in the Continent who were most blessed by the gods. At the end of the war, some of the elves undertook a mission to guard the gateway to the demon realm located in the Dark Continent. These Elves that went to the Dark Continent came to be known as Dark Elves.
As the Three Goddesses planned, the gem was sent to the Continent to restore life. All went according to plan and the gem helped the Continent become habitable again.
Living beings in the Continent named this gem El and named their continent Elrios.