You Alone Can Defeat Evil tells the story of a world recovering from the Great War, where colonial powers and rebellious colonies clashed for control. At the final battle in the colony of Eathabar, rogue Sorcerers of Eskilon summoned a destructive force – the Great Demon, an embodiment of hatred, which threatens to consume humanity.

As one of the rogue sorcerers, the player is haunted by their role in unleashing this terror. Now, the player must journey to the Shrine of the Cosmos, where the Great Demon channels its power to corrupt the human heart. Only by mastering the soul magic of Eskilon can the player hope to defeat the demon and restore peace to the world.