One of the few habitable planets in the Eta Salva system, Mirios appears dead from orbit. Endless muck, no geological activity, and a dense hazy atmosphere.
However once on the surface, the haze lifts slightly and reveals the great swamps. There is animal life on Mirios, though it is mostly subterranean, living a life in the deep muck that permeates this small world.
There also appears to be ruins from a long gone sapient species, and vast megastructures have been detected below the planets surface. The ground is too wet to reach these structures.