In "Cross My Corpse," no demons or monsters came into existence from nothing; every one of them had an origin.
Though demons, devils, ghosts, and monsters were often mentioned together in the game, they were actually somewhat different, jointly forming the game's monster system.
Demons generally referred to animals and plants that had mutated due to aura, such as Carrion Hyenas, Dire Wolves, Hungry Vultures, and Mad Vines. They were commonly found in "?" encounters along the road.
Devils specifically referred to humans—people who had eaten rare treasures or grown stronger through comprehending aura, then gone on to slaughter living beings, murder people to refine bones, and take hearts to forge artifacts. Such people were evil toward all living creatures—especially spirits. They were relatively rare, but whenever they appeared, they were at least minor Boss-level threats.
Ghosts specifically referred to resurrected corpses and resentful dead. They were also the most common monsters in the game, and formed the core of "Slaying Demons and Eliminating Devils."
Monsters were lifeless objects that had gained intelligence due to Aura Resurgence. Many spirits belonged to this category. Most monsters did not affect humans, but like devils, if they truly became enemies, they were at least Boss-level threats.
For example, the Azure Dragon Crescent Blade after Guan Yu was killed in 220. In several saves Ren Suo had played before, he could encounter it in a "?" event as long as he reached Eastern Wu territory.
The moment it appeared, the Azure Dragon Crescent Blade attacked directly. Its attack covered the entire map and dealt area damage, with 100 Attack and an additional fourfold single-target critical hit...
Ren Suo strongly suspected that the Azure Dragon Crescent Blade could be negotiated with, perhaps even recruited and used.
Just like obtaining the Goddess of the Luo River