This Material development was inspired by Ryse Moss Tutorials and Shadow of Colossus. I tried to create a Shells Master Material that can be used for variety of situations for Unreal Engine 4 and here are some breakdowns
Main feature is the Fuzzy on BaseColor
Able to control with typical Fuzziness function like Fuzzy Power and Core Darkness
Red Vertex channel is used to gradually make the BaseColor darker towards the bottom and also controlling the amount of the Opacity Mask
The highest shell will have the highest value (1) and the higher the value, the brighter the BaseColor and more Opacity was masked. These 2 features are needed to nail the Fuzziness feel
Green Vertex channel is used to control the overall shell offset, also have controls over the edges masked using Vertex Alpha, offsetting in general or fan out the edges
Same with Red Vertex channel, the Green Vertex channel is painted in a gradually manner, but can be modified if needed
Blue Vertex channel is used for color variation
Color variation is a typical setup with full range of color available
Alpha Vertex channel is used to further masked out certain area or edges, useful for blending with other assets
Detail Normal can be add to give further unevenness of the surface, or switch with Grayscale Height Map
Animation is a typical panner with time and some noise for the secondary animation