For century, the protogens were used as nothing be slaves by their creator, the Primogenitors. Using the "ARC" to control them. The protogens would lack conscious free will. But years later, the "Rare protogens" have betrayed their creators, and trained themselves to use power of the Arcaite to free the common and uncommon protogens. Now the protogens have true free will. This has resulted in an all-out war. And it would be known as the Protogen Rebellion.