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"Most beloved are the fissioneers, who vaulted us to power on a world without petrochemicals. May they forgive the many stories of horror we have told in their memory. May they in particular forgive the lurid stories of the molten lead reactor, and the twelve who were impaled to the ceiling by their control rods, and the Core That Stalked."
Imponent I, Marasenna

The fissioneers were a group of Awoken engineers responsible for building nuclear fission reactors during the establishment of Awoken civilization on the Distributary.

The fissioneers are the subject of many apocryphal stories among the Awoken, many of them tragic. Among these is a tale featuring an entity known as the "Core That Stalked,"[1], a name also seemingly used to refer to the Aphelion during the RSS Amestris incident[2].