I appears to be a split color, black underneath and a deep purple on top. At least on my monitor is seems as such. Look at the underside of the spikey legs and you'll notice the lack of glitter yet its present on the top sides. Probably best using a twin injector for this.
It seems that some color comes through the black so I'd start off with a medium smoke as the bottom color and thicken it as needed.
The top I'd use either Do-Its Florida Grape or black grape from somewhere else, keeping the color fairly transparent and adding some purple glitter, maybe start with .015 size.