A field guide entry for something that shouldn't exist
Folklore bestiaries describe monsters in a practical way: where they live, what they do, how to avoid them and what they fear. That practicality is what makes them believable. This creator writes creatures in the same register, as if an investigator had compiled the notes.
The habitat influences the creature's appearance and behaviour, and the threat level describes how dangerous it is within the fiction. Every creature is invented; the generator does not describe real animals or real folklore figures.