Parasitic Selection and the Roundworm Gu Experiment

Parasites

The largest and most old-fashioned category of large-scale pathogens in the Old World,

Unlike microscopic pathogens such as bacteria and viruses, parasites were generally larger in size and retained their own independent autonomy.

Bacteria such as Death Plague Mist Bacteria and Fish Scale Tetrad Coccus, or viruses such as Mad Shell Virus and Blood Plague Virus, formed a complete whole after infecting an individual—the "Sick One."

There was no concept of separating the host from the pathogen.

Parasites were different. Most of them could be classified as part of the macroscopic world, and some mutated, ultra-large mimetic parasites could even move about freely like humans.

Mahart J. Nash, the current supporting performer of the Fear Circus, was one such ultra-large Amoeba Brain Worm. He directly mimicked the appearance of a human without needing to infect a host, and was even far stronger than his kind.

Parasites cared deeply about their autonomy,

Strictly distinguishing between the concepts of "self" and "host." They even frequently treated other Sick Ones as hosts... In the early days of the Old World, compared with the madmen of the Blood People, parasites were more hated and condemned by the Sick Ones.

To control the parasites' proliferation and wanton parasitism,

the Old World's central authority sent direct signals to a large number of parasites that had reached the Silver Ring level, asking them to participate in a special selection competition held within the world's core.

The strongest one would be selected as the Plague Lord, who would establish the Source Plague Zone, integrate parasites of different categories, and restrain and control them. The Plague Lord would be responsible for managing them.

Any parasite that refused to submit to discipline would be hunted down and killed.

Since all the different categories of parasites were integrated together, the