Silentium

These droids were built by a star-shaped organics species to mirror their own form, analogous to how sentients of humanoid shape create bipedal droids. When a radiation storm, triggered by a nearby supernova, extinguished the organics, their droid creations persevered.

These droids went on to replicate and improve themselves, establishing a culture rooted in the prime numbers five, seven, and eleven. A significant number adopted geometric forms, with the circle being revered as the "holiest" shape. The most knowledgeable members of the droid species, numbering in the thousands, constructed massive spheroid bodies measuring fifty kilometers in diameter. Among this giant variety were two key figures, The One and The Other, while the remainder were collectively known as The Rest.

This emergent culture, defined by order and symmetry, inevitably clashed with the Abominor, a group of chaotic, self-constructing droids. The two droid factions engaged in a galactic war, disregarding the galaxy's native organic life until the Yuuzhan Vong retaliated, forcing both droid powers to flee.

The Silentium eventually discovered a new galaxy to inhabit, settling in an area that Humans would later designate as the Unknown Regions. Their secluded and conventional lifestyle eventually led to boredom, prompting them to create young droids in the likeness of their organic creators to explore the galaxy.

Some of these juvenile droids ended up in the oceans of Mon Calamari, as the mechanical entities referred to as nano-stars bore resemblance to the description of the star-shaped race and were deposited by a massive metallic sphere. The scout known as Vuffi Raa then experienced a diverse range of adventures with various masters, including Lando Calrissian.

In time, the Silentium sought to reclaim their "child," revealing themselves to the wider galaxy during the Battle of ThonBoka. Demonstrating their formidable power by obliterating the Imperial cruiser Recalcitrant, they retrieved Vuffi Raa.

The Silentium permitted Vuffi Raa to revisit Calrissian on multiple occasions, and the colossal spheres continued to be observed across the galaxy, including a sighting by a hundred thousand individuals during the Priole Danna Festival on Lamuir IV. While they exhibited no inclination to intervene in galactic affairs, their new home system is thought to be located somewhere in the outer rim.

Daniel Wallace, the author of The Essential Chronology, intended the Silentium sightings across the galaxy to be a reference to contemporary UFO sightings.

According to Dan Wallace's endnotes in The New Essential Guide to Droids, the conflict between the Silentium and the Abominor is heavily suggested as the underlying cause of the Yuuzhan Vong's technophobia. This was subsequently corroborated in the second installment of the blog series The Droids Re-Animated.