What was the most terrifying thing among the undead? A Demigod-level lich? A fearsome bone dragon? A black knight with outrageous combat power? None of them. Some said there was a legend among the undead races: when an undead creature grew powerful enough, it would become a monarch, the supreme existence among the undead.
Yet undead creatures did not fear monarchs, because such lofty beings were simply beyond their reach. What they truly feared was a kind of insect. There was nothing particularly special about these bugs themselves. They were not powerful; even a skeleton could easily crush one to death.
But they lived in swarms, numbering tens of millions at a time. Each was at most the size of a thumb. Their defenses against physical attacks were extremely low, yet they were nearly immune to all magic damage. Even if a Demigod-level lich continuously unleashed powerful spells, killing a million of them at most would probably exhaust all its mana.
Moreover, undead control magic had no effect on these insects, because they had no souls. Yet they possessed an almost obsessive longing for souls. They craved any creature with a soul, as though their subconscious minds desperately yearned to devour souls and make themselves whole.
Some scholars had once believed that these insects were formed from the obsessions of people whose souls had shattered. Of course, that was only a theory. It was not as though no one had ever captured these insects for study, but the conclusion was that their souls simply could not be found. Even reading their memories was impossible.
These insects would only gather together and wait for humans, creatures, or even undead with souls to draw near. Then they would rush out and devour their souls!
These were Death Soul Worms, the lowest rank