Arkana are a series of genetically engineered female beings, (with one exception), technologically augmented to adapt on harsh environment of New Earth with duty to defend humans and help them in retaking their former home. Each of them is unique and has its own skills, weapons and mechs which help them to fight with any enemy they may met.
When Naraks began invading Earth, nobody knows how to fight them. Humans armies were all killed one by one, their weapons didn't even scratch them. Then, hard decision was made - to use nuclear weapons. But even that didn't stop Narak from coming. Finally, humans choose to destroy Naraks and themself as well by using nuclear bombs to complete destruction.
But in the meantime and before Narak invasion, company known as Genesis Corp began their work on cloning adults. When they became able to do so and when Earth was near to complete destruction, they were contracted to create the Ark Project. Hidden, time-delayed and fully-automatized cloning facillity. In two hidden bases they created genetically diverse human beings which will be one day able to return on Earth's surface and recolonize it when nuclear winter will end.