The Contraproprioceptive Virus (CPV) was a tailored virus designed to crash a specific cladist on the System. For most of the System's history, it was the primary method of killing individuals sys-side. Viral constructs were often knives, syringes, or other menacing objects.[1] In order for an instance to be affected, the construct must have instilled an anticipation of danger and cause some kind of injury. Poisons and benign objects were inadequate because they did not draw a self-evident connection between the viral construct and the victim; the symbolism of killing was the vector by which CPV afflicted an instance.
An instance afflicted with CPV suffered an unravelling of their sensorium, subjecting them to alien and inhumane sensations that very often coerced them to quit. Those who endured eventually crashed as a consequence of CPV, and the resulting core dump was seldom recoverable. Particularly savvy victims could manage to fork away the virus, although they had only seconds to do so and a great deal of agony to grit their teeth against and often suffered long-term instability regardless.
CPV was seldom used, and the means to create viral constructs is a closely-guarded secret. After the Century Attack, the bug that enabled CPV to function was removed, rendering all viral constructs inert.[2] On the Perils of Memory made it known to the public, and most cladists after 190 would recognize it if they saw it in use. Crashing as a result of CPV was not a subtle affair; the afflicted instance dissolved into voxels as their avatar became corrupted by their unravelling sense of self. Most victims screamed through the entire ordeal, their voices increasingly distorted until they finally quit or crashed. Witnessing the use of CPV was as traumatic as witnessing a brutal murder because one had witnessed a brutal murder.