Blue Star encountered an unknown energy impact, and humans around the world collectively traveled to the "Broken Star Islands" - a dangerous world composed of tens of thousands of floating islands. The islands are separated by corrosive "turbidity currents", and natural disasters such as acid rain, magnetic storms, and beast tides will periodically break out. Each person is bound to a "survival bracelet", which displays basic status, backpack space and regional channels. Materials can be traded but there is a risk of fraud; the island will sink slowly, and "floating island cores" need to be obtained regularly to maintain its existence; some islands contain "civilization relics" containing remnants of pre-civilization technology.
