In a parallel world facing resource depletion, a mysterious island world descended upon Earth twenty years ago. All those who reach the age of eighteen can enter and become island lords. By defending their islands, they can develop resources and even obtain extraordinary materials, achieving immortality and eternal youth. The protagonist, a time traveler, arrives during a crucial period—a mere twenty years after the island world's arrival, an era of great danger and uncertainty. Humanity has barely managed to survive. Starting with a single island and a unique enlightenment system, the protagonist commands countless ferocious beasts and manages countless islands. Everything in the world can be enlightened.