I almost made this a game but I couldn't think of a good gameplay for it, so I decided to just keep it in literal form.
So as you can guess this is a story revolving around Atlantis but also another sunken kingdom called Kumari Kandam.
Far back before human civilzation had truelly begun a large meteor crashes near a group of tribes in what will become Europe. The people discover what the meteor really is, and after learning it's true purpose the tribes uses the power of the meteor to turn their tribes into the most powerful kingdom in the world.
They conquer any people that stand against them, but that all changes once they encounter the Kumari Kandam; a more natural kingdom that evolved into an anicent world super-power unlike the Atlantians. The two kingdoms erupt into a war and the Atlantians find themselves losing it. To prevent this they use what they now call their god to sink the Kumari Kandam into the Indian Ocean.
Few Kumari survived and the remaining warriors form a small group that later become the Kshatriya, called Trimurti. These warriors travel to the captial of Atlantis, discover the 'god' and in a sacrifice to their people use it to sink the continent of Atlantis.
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So now we move on the present day, and two factions are now seeking the God of Atlantis; one to use it as a weapon and the other to destroy it.
The Trimurti Kumari, desendents of the original Trimurti, are in a consent war with the Atlantian desendents to find the 'god'.