Tales of Agarthia Book 1: Journey

Long ago, the Majin lived together in harmony with the Humans of the world. Their ability to control Machina and cast magicks was a wonder for all. But one day, the Kings and Monarchs decided that the Majin were a threat, and so began the Majin Massacre.
Majin, regardless of age, gender, or social status, were slaughtered, and Kingdoms, which had been on the brink of war, came together to aid in the slaughter. The Majin refused to fight back and went into hiding, never using their magicks again and teaching their children the same.
But one day, everything changed, and it seemed as though only the Majin could help. All of them refused, all except one.