Taking from the idea that Skeksis are unhealthy and that being away from the Crystal and not using it actually makes you healthier, plus the whole 'SkekVi actually has sex' thing going on in the story (link below)... well, fertile eggs triggered their body going into full mating display. I used a lot of references from various birds, and I'll work on a full body pic to show the way the 'quills' turn into a feathery fan (a la argus pheasants or peacocks). tl;dr: Healthy skeksis are very colourful birds!

The dark purple and black are meant to be that lovely iridescent you get with bird feathers. It's hard to draw ofc.

Story Here: https://archiveofourown.org/works/35645554