The Markers broadcast an electromagnetic signal, originating from the Moons themselves, that mentally affects intelligent beings. It is unknown if the Moons specifically target worlds that show promise for intelligent life, or, as theorized by the Unitologist leader Jacob Danik, if the Markers are actually responsible for encouraging the evolution of intelligent species. The Moons consume new worlds by sending out Black Markers, which travel through space and impact planets in the case of Earth, the Black Marker was carried inside an asteroid that struck the Yucatan Peninsula around 65 million years B.C. The Brethren Moons, though their origins are unknown, are a series of moon-sized creatures throughout the galaxy that consume all organic life that they encounter through the use of their Markers. Due to their agenda the Brethren Moons are the central antagonists of the Dead Space franchise. They are believed to be the final life cycle stage of the Necromorphs.

The Brethren Moons (or Brother Moons and Blood Moons) are the source of the Marker signals. The Brethren Moons to Isaac Clarke and John Carver, Dead Space 3: Awakened “You can kill the prophet, but you can’t kill the god! Your chance to warn the Earth has come and gone.

Brethren moon dead space earth