My fate of a lifetime even in the Grey's mansion

The world is filled with chaos, suffering, destruction, and secrets, and technology is the very center of it the roots of all problem even in Millennium years ago, until the guardian of earth awoken from its slumber seeing how destroyed its land was, and as a girl sympathize with the world for not having time to take care of it she took her life, in exchange of what, a chance for humanity, the world gone drastic changes where a large tree grew as mountains and mana overflows, and it was the start of a new era where magic and mythical beast and a new start begins