The Witch and the Hundred Knight

Fed up with being unable to travel beyond the borders of her swamp, the witch Metallia forges a contract with the legendary Hundred Knight to help her realize her ambition of spreading her swamp throughout all of Medea. As the Hundred Knight, your mission is to do whatever your master, the Swamp Witch, commands. Explore the world, destroy Pillars built to prevent her swamp from preading, and wreak indiscriminate havoc. However, in the back of your inhuman mind, you begin to wonder... What prevents Metallia from leaving the swamp? Why do the other witches shun her, and how can she survive in a swamp that is notorious for how poisonous its fumes are? Is Metallia really a witch to respect, or is she one to fear?