I decided to go with a teal and rusty metal palette. I did not want to go with black, as I wanted a ghostly effect and avoid it looking like a typical wraith or shadow. The robes and cloak were painted with teal mixed with black, then lighted with subsequent layers. The armor is a base of Vallejo Tinny Tin, with some Vallejo Gunmetal on top to make it appear ancient and rusted. The sword is layered with grays, with black and red on the hilt. I wanted to imply that the sword is enchanted, and did not suffer from neglect as the armor has.
Conclusion: I only had a vague idea in my head when I started; I was sure of the colors I wanted to use, but not how they were turn out. I thought about attempting a glow effect on the ghost, coming out from between the plates of armor, but with the complicated overlapping shapes it seemed too complicated to execute properly. I like how the figure turned out, and I'm glad I took the approach I did.
Next week's figure is 77158 Arrius the Black, Skeletal Warrior, also from the Grave Danger set.