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The embodiment of Anhenfil, the monster world.

The embodiment of the predatory world, the world of monsters, and so on, Anhenfil.
Initially, it did not exist, and monsters were simply sent out by newly created beings who found and brought home those who seemed to their "mother" to be saturated with impressions and sensations that the world so desired. In fact, such victims were often Nightmares who had gained experience and understood that it was better to live without standing out too much, pretending to be ordinary inhabitants of one of the worlds whenever possible.
But it wasn't very effective, and then she appeared. A creature without a will of her own, whose feelings, mind, and memories were one with the world that had created her. The price for this was significant — she couldn't leave the world for long, she only had enough time for a short visit to one world, and then she was pulled back. But that was enough to guide the hunter to the right world and show him who he (or they) had to bring home. Inside the world, she was one with that world—she could appear anywhere in it, knew everything that was happening, and could create and destroy her own creations.
Over time, something akin to beliefs developed among the Nightmares, though it could not be called a religion, but rather superstition. They called upon it for help, both in their own world and beyond. They feared encounters with it, for they almost always ended in death. They knew that nothing could be hidden from it.
This continued for a very long time, until one Creator, Varog, took what was considered an impossible decision and connected the two worlds. His dying self, which had rejected all his attempts to save it after the disappearance of the previous Creator, and Anhenfil. In essence, he gave the Nightmares the opportunity to freely visit one of the worlds, as Anhenfil became a kind of mirror image, or even the "underworld" of Nararis. A place where monsters appeared and dragged away the inhabitants of the world. Who now had to hold on to their native world in order to survive. Otherwise, the predatory world would simply devour both Nararis and its inhabitants.
But there was another complication in all this: the Guardians of Nararis, or rather one of them, Rumon, turned out to be from the same world. In fact, this is what enabled Varog to carry out his plan—through a creature connected to both worlds. Urt, his companion and inseparable part, changed the world, turning it into a Nightmare as well, giving it a second, "demonic" form of a monster. Perhaps in this form, the Guardians protected the worlds from outside intrusion even better than before, but now a different fate awaited them. They were appointed hunters, those who would have to find the Nightmares scattered throughout the worlds and bring them home. So that Anchenfil could accumulate enough strength to absorb the world connected to him.
And Lifnehna herself created a second form for herself, one that was not so frightening, in order to communicate with the inhabitants of other worlds. However, now only she, Rumon, and Urt had such powers, and even those were limited to two forms; all the other Nightmares were locked in the forms they had at the moment the worlds merged.