Trapped Between Cages

In 4050/5/20 Earth has been attacked by an evil villain Named Dema and her army who invade looking only for twelve teenagers Tskusuda, Kuson, Sakato, Austin, Kaguya, Jalen, Yamoka ,Kamora ,Kushi ,Mokua ,Michio, Madoka who don't remember anything after they got to Earth because they whipped their memories, but they used to be one of the strongest forces you could ever come across but after they thought they defeated Dema she aroused once more to take her revenge for her planet people and parents so she planes to take there power and combine it with hers in which will make her be seen as a god and she will summon the {the driven Tarrasque.....the dark beast} and destroy Earth as an example for all life as we know it. And they only one shot at permanently stopping Dema