I Went to Farm on a Small Island, but Became the Overlord of the Universe

Li Dan grew up in the countryside, eating at neighbors' homes, and was looked down on everywhere in the city. He didn't care about their prejudice, but it kept derailing his plans to take life slowly, until one day he acquired the System left behind by the destruction of the only ninth-level civilization. From then on, his life spiraled out of control. He bombards the Sun Nation, points a gun at the world's police force, and grows so powerful that aliens no longer dare invade Blue Star.

Yet in a corner of a small island, Li Dan cries, "All I want is to farm! Aaaaaah!"