That I Am Fierce and Capable? the Goddess Who Built the City in the Apocalypse

[Weird arrival + high martial arts apocalypse + gravity power + building a floating doomsday base + no system + no virgin] Above the dilapidated land, a floating island is slowly moving. This is the last piece of pure land left after the entire world was invaded by unknown creatures. Natural disasters emerged, strange invasions occurred, and the world was devastated. The end is coming...! Human beings have awakened various powers. "Self-monitoring begins, analyzing..." "Monitoring results: SSSS level superpower." "Type of superpower: special type of unknown gravity control." "The introduction is weak, please read the text.