causal: (adj.) of, relating to, or acting as a cause
The causality virus, designed by the Highbeam Multistellar’s most skilled engineers on Bellatrix, carries on the in the same weapon-of-mass-destruction tradition as the Bellatrixian plague fungus. Despite its name, the causality virus is not an organism of any sort. Instead, it is a nanotech weapon system built to infiltrate energy systems and disrupt the causality of energy transfer within those systems.
Like almost all nanotechnologies, the causality virus is self-replicating. The initial payloads are delivered to the target areas via conventional means, such as a missile. The virus then spreads, seeking out energy systems. It “infects” these systems, disrupting energy transfer by using that energy to fuel the nanotech’s self-replication. Once the “infection” within a system reaches the point at which no further energy transfer occurs within that system, the virus seeks out a new target.
The virus devastates target areas. Obviously, it shuts down all technology more sophisticated than simple machines such as waterwheels. Organisms also have energy systems, and the causality virus attacks biological processes as well. The effects on a human, for example, produce blindness and deafness almost immediately, rapidly followed by paralysis and then the complete cessation of all biological functions. Death is swift and almost painless.
After the causality virus has done its deadly work, coded broadcasts from orbital assets signal the nanotech to self-destruct by shutting down its own energy systems. This permits invading forces to move into the previously infected areas to clean up the dead and reactivate technologies affected by the virus.