Eclipsium begins in a sunless, self-consuming world. A desperate protagonist known as the Wanderer is forced to search for a mysterious figure called She. Their first-person journey takes them through a series of surreal, ever-changing locations, including hellish tombs and cathedrals of flesh. The environment is unstable, and the hero must sacrifice everything to continue their search. Each location becomes a psychological test in an atmosphere of mystery and existential horror.