For the Faceless ape from Pongo Labyrinth, It’s design was heavily based on an illustration by Heinrich Leutemann of a normal orangutan drawn back in the late 1800s.

Another design choice for the faceless ape was to lean harder into the uncanniness as it’s not a real ape. Specifically with textures on the faceplates and hands. As well as removing fingers/toes on the hands/feet and having the nostrils facing the wrong way.