Lone Peak Fortress: Doomsday Survival Chronicles

Half a year after the apocalypse broke out, former ranger Rex established a steel fortress on a solitary peak in the Rocky Mountains. He successively rescued the tech genius Ethan and battlefield doctor Sophia, and the three of them defended against the frenzied siege of marauder leader Cole on this post-apocalyptic island. Amid scarce resources and bloody conflicts, Rex must use extreme tactics and ruthless methods to protect the last refuge.