Two more detailed sets of drawings and descriptions: Mutant Satyr and Nightgaunt.
The Satyr is basically the result of human (or otherwise humanoid) exposure to extradimensional energy sources (i.e.: a Great Old One, a gate, artifact, etc.) or extradimensional ectoparasites.
Mutations can be guided if under a controlled environment but often result in catastrophe. The images show the creature’s concept art, an abdominal dissection and a variant sample (possibly used as cattle).
The Nightgaunt is a slim, elongated inhabitant of the Dreamlands. They nest in high peaks, but are fond of nesting in caverns in mount Ngranek. They are some of the most mysterious creatures of the Dreamlands, and their physiology is still mostly unknown.
They abduct hikers and intruders, usually dropping them in the dimensional underground. Images show the concept, manus and skull detail.