The galaxy is ancient beyond human reckoning. Billions of stars coalesced, ignited, warmed planets, and then died long before the rise of humankind. A handful of these dead stars and forgotten worlds are home to the wreckage of civilizations vanished for millions of years-the ruins of the assorted alien species collectively known as Precursors.
By most estimates, the earliest Precursor races couldn’t have evolved in the Milky Way galaxy until about one and a half billion years ago; the first generation of stars created in the formation of the galaxy had almost none of the heavier elements necessary for life in their planetary systems. The earliest second-generation stars needed a couple of billion years for Earth- like planets to form from the primordial soup and develop intelligent life. On the other end of the scale, the most recent Precursor races vanished or died out within 100,000 years. At most, the remains of perhaps five or six Precursor races have been discovered in all of human space; the Precursors of Mantebron are locally known as the Glassmakers.
The Glassmakers lived hundreds of millions of years ago, in the days when High Mojave still had seas and a full atmosphere. Their ruins show a high level of silicon-based technology, but little metallurgy. Hundreds of xenoarcheologists are now studying the Glassmaker ruins across Mantebron, but results have been disappointing so far-the Glassmaker ruins are just too old.