2300 years ago, the Space Alien survey fleet Σ Archive was declared Irrational by the Lords of Logic, and a directive was announced to liquidate the ruling clone line. Σ Archive responded in aggressive fashion. The majority of the fleet star-jumped to the heavily-populated Arcton system, entered that sun’s convection zone, and triggered their jump drives: the resulting black hole consumed the entire system, killed over 2.4 billion Space Aliens, and destabilized a region of space measuring over 10 pc³.
The remainder of the fleet (containing the Σ Archive leadership) star-jumped to the CARCOSA system, broke through the planetary blockade, and made landfall southwest of the Yathlogthotep Forest. They were well on their way toward concluding alliances with several entities confined within the Black Abomination of Nyarlathotep when disaster struck: an unprecedentedly large swarm of Giant Jungle Ants (4 million+) erupted from the nearby jungles and devoured everything organic in a 50 mile radius. Thusly was the Σ Archive liquidation order belatedly upheld.
In the following years, Men of many races returned to the area and picked over the remains of the Σ Archive base. Little more than scrap metal remained to be salvaged, but a cohort of Black Dervishes uncovered an intact vault with a rare trove: several hundred Selenium Eruptors in perfect condition. These powerful hand weapons proved decisive in the Black Dervishes founding their Conclave of Flames, an empire that pillaged unchecked for over a century until its armies disappeared into the Empty Maze far to the north.
Today, Selenium Eruptors are among the most common of Space Alien weapons to be found on CARCOSA, though still comparatively rare: