Art by Hannah Bruders
I always planned for Skath to be a shape-shifter, to be able to reflect the difference in between different individual's fears. He started out looking like Slender Man, choosing that form because he liked its look. However as I developed his personality further, he took on a more youthful air and his initial design seemed to undercut those traits. His second design gave him a lot of opportunities for surprises and jump scares while being consistent enough to keep descriptions simple.
As a spirit, which has more in common with a biblical angel than an anthropomorphic personification, he also needed a shape that was less third dimension focused. In a sense, this is his true form or at least the form he uses most often when talking to those above the third and fourth dimension.