The Great Deluge (sometimes referred to as the Great Flood) was a geological catastrophe that occurred some 9,600 years ago.
A giant skull-shaped meteor from outer space crashed into the Earth somewhere near the North Sea. The impact was so tremendous that it caused worldwide geological upheaval. Tectonic plates shifted, yielding massive flooding so intense that it caused the entire continent of Atlantis to sink beneath the waves. Though nearly all of Atlantean culture had been wiped away forever, those of the capital city of Poseidonis managed to survive due to the erection of a giant dome that shielded the entire city. It was believed by some, that the destruction of Atlantis was the result of Suula - Goddess of the Sky -- who took offense to the creation of the dome that cut Poseidonis off from the skies above. These Atlanteans managed to eke out a life for themselves, though they could never again leave the safety of their city.
Some Atlanteans however, found an alternative in the priest-mage known as Shalako. Shalako used his magic to protect his followers from the crushing pressure of the ocean depths, and they migrated from Poseidonis and re-established a colony in the ruins of the sister-city Tritonis.
A few short years after the calamity, Atlantis' monarch, King Orin, had his scientists develop a means so that his people could survive underwater, without having to stay within the city. The experiment was a success and the serum transformed the Atlanteans from normal human beings into aquatic amphibians who could survive the ocean depths and draw oxygen from water to breathe.
Most regarded Orin as a strong and benevolent leader, but there were those, including his brother, Shalako, who felt that Orin's compassion made him a weak ruler. Orin was the first to put together the Atlantis Chronicles and assigned Albart-Son-of-Yarrow of Ancinor the task of maintaining a faithful history of their home country.
Due to the machinations of Shalako, the citizens of Tritonis evolved into a race of Mer-people. At first, the former Shalakites adapted to this mutation, until they discovered that the changes were being passed down to their children. The most severe example of this effect was the Atlantean prince, Kordax. Kordax was born a hideous, green-scaled mutant with blond hair and the ability to telepathically control the creatures of the sea. The existence of Kordax caused a schism throughout Atlantis as by right of ascension, he was the first-born heir to the throne. This conflict erupted into a massive war between Poseidonis and Tritonis.
!!! What happened after that ?? I mean, how did he become king of Atlantis ??? 
