Shroud

The Shroud, also known as the "The Silent Ones" by the Beta, are an enigmatic race that was responsible for the destruction of the Beta society, as well as possibly many other worlds with life.

Biology
The most common word attributed to the Shroud is "unknown." The very nature of this life form—speechless, faceless, elusive—makes it one of the most powerful and least understood beings. The Beta were the first to tell stories of the "Silent Ones" after spotting mysterious, stealthy apparitions during their voyages along the edges of Dark Space. However, many of the details surrounding these sightings have been blended with folklore and are likely exaggerated. It wasn't until the Goo encountered the Shroud during Humanity's Pathfinder Program that its nature was explicitly defined. By analyzing the Shroud mathematically, the Goo understood it to be a parasite with an ever-growing appetite for energy. It realized that, if left unchecked, the Shroud would drive the universe to nothingness—or in Goo terms, zero. After almost total annihilation, a fraction of Goo escaped. It fled as fast as it could, harboring with it knowledge that this specter could one day emerge from the shadows.

History
The Beta initially believed that the Goo themselves are the Silent Ones, as the idea of a spreading Silence fits their expansive and initially sinister character. But it is revealed by Singleton that the Goo was actually opposing the Silent Ones and trying to save other lifeforms.

Shortly after a truce between the Beta, Humans and Goo, the Shroud descends on Ecosystem Nine and thrusts it into war once again. The actions of this alien life form make its intent immediately clear: to drain the planet of energy until there's nothing left. It's a threat all three factions must face together—or be completely destroyed.