The setting of Xenoblade Chronicles originates in a world that was nothing but endless ocean until two titans, the Bionis and the Mechonis, came into existence and battled each other until only their frozen corpses remained. In the eons following their battle, they became the home of multiple forms of life. The Bionis is home to organic lifeforms, most prominently the humanoid Homs, who are virtually identical to humans both in appearance and biology; the diminutive and furry Nopon; and the avian humanoid High Entia, whose lives span centuries. Conversely, the Mechonis is home to the mechanical humanoid Machina, whose lifespans span several millennia. A substance known as ether is given off by all life forms, and can be used both as a form of magic and as a method of fuel. The Monado – the namesake of Xenoblade – is a mystical ether-controlling sword used by the Homs in the battle against Mechonis, which grants visions of the future to its wielder when fully controlled. The game's main cast of characters is Shulk, a young Homs scientist who lives in Colony 9 on Bionis; Reyn, one of Shulk's childhood friends and headstrong member of the Defence Force; Dunban, a former wielder of the Monado and the brother of Shulk's childhood friend and love interest Fiora, who also joins Shulk; Sharla, a medic and sniper from Colony 6; Melia Antiqua, princess of the High Entia and a High Entia-Homs hybrid; and Riki, a Nopon chosen as the hero of his village.