No Game No Life

Sora and Shiro, a sibling duo of genius shut-in gamers known online as "Blank," beat the god Tet at chess and are summoned to Disboard, a world where wars, borders, and disputes are settled entirely through games. Humanity in Disboard has been pushed to the brink of extinction by fifteen stronger races, clinging to its last city, Elkia. The siblings set out to unite the sixteen races under humanity's banner by winning every challenge they face.