This is a fanfic I really like It's not mine it's by a guy named Waffles I'm just sharing it so you all can check it out

At the start of the 20th century, humanity made a grave decision, killing the husband and unborn child of Dioram, an ancient and powerful sorceress from a god-like species predating mankind. Left bereaved and disillusioned, Dioram lost faith in humanity's worth and sought to wipe them from the Earth. Embracing mankind's fears, she made vampires and werewolves real, and some willingly turned into various monsters, seeing Dioram as a mother figure who would birth a new world. On the day of the signing of the armistice Mother's followers unleashed hell upon the Earth, wiping out over half of humanity in just half a month. Mankind's extinction seemed inevitable, but some of Mother's children took pity on humans and rebelled, leading to a war that lasted decades. However, hope emerged when Archangel Michael came to their rescue, accompanying him was a human-demon hybrid name Vexsoul to confront mother. Though Mother was mortally wounded, she found refuge within an impenetrable dome, slipping into a dormant state. The world transformed into an unrecognizable wasteland dominated by monstrous creatures, and the thirst for war endured. Two centuries later, humanity teetered on the brink of extinction, oppressed by tyrannical governments and monstrous beings. Among the chaos, the Half-Blood Creatures-a fusion of human and monster blood-held the fate of humanity. This is the world of "The Half Blood" series, where a glimmer of hope remains amidst the despair, and an unlikely hero holds the key to humanity's future.

At the beginning of the 20th century, Humanity would make one of the worst possible decisions that they could make. They would kill a husband and The Unborn Child of the most powerful entity in our world, an ancient being known as Dioram. A powerful sorceress, from a God-like species that existed long before mankind. She was one of the last of her kind that lived amongst men peacefully living out of sight until mankind took her family away from her. No longer believing mankind was worth saving or helping, she concluded that the only thing left was to wipe mankind off the face of the Earth so no creature may suffer from mankind again. She sought out our greatest fears such as vampires and werewolves and vowed to make them real. Finding people no longer Satisfied Or wanting to be human willingly allowed themselves to be cursed and turn into every various monster imaginable. They begin to admire the dioram and begin to call her mother; they believe that she will birth a new world void of the plague of mankind. After the end of the Great War the day of the Amethyst. Mother's followers unleash hell upon the Earth More devastating than all of Mankind's Wars combined to the human populace in a span of half a month the followers of Mother wipe more than half of the human population off the face of the Earth.