Ultors

Ultors are a fictional species featured in the science fiction franchise known as "The Expanse". They are an advanced, insectoid alien race that predates humanity in the Milky Way galaxy. Ultors are characterized by their highly sophisticated technology and their long-term, often inscrutable, plans. While not explicitly depicted in great detail, their presence is felt through the remnants of their technology and their influence on galactic events.

The Ultors are believed to be responsible for the creation of the protomolecule, a mysterious alien biological agent that has profound and dangerous effects on organic life and technology. The protomolecule serves as a central plot device in "The Expanse," driving much of the conflict and exploration within the series. The Ultors' motivations for creating and potentially disseminating the protomolecule remain largely unknown, adding to their enigmatic nature.

Their technological prowess is evident in the advanced nature of the protomolecule itself and the colossal alien structures discovered throughout the solar system and beyond. These structures, often referred to as "rings" or "gates," are believed to be remnants of Ultor civilization, facilitating faster-than-light travel between star systems. The vastness of their reach and the age of their civilization suggest a profound impact on the galaxy's history. The ultimate fate of the Ultors is also a mystery, leaving their full story open to interpretation and further discovery within the narrative.