RWBY: Hyousetsu Teikoku S01

Legends and stories that have remained from the past tell the tale of humans who were consumed by their own bravery against lowly and corrupt creatures, unaware that they were born into a merciless world. Meanwhile, the creations of darkness, beings without spirit or intellect, only brought destruction, and their attention was drawn to humans and their creations. An unfair war broke out between the two groups, a war in which the power disparity was so great that it pushed humans to the brink of nonexistence and destruction. However, humans were able to create, after some time, a tool with their ingenuity that could perhaps make the conditions of the struggle more just. A tool called "earth", rich in energy. After the war, humans became more civilized. But darkness still has power...