Many thanks to http://www.thingergyinc.com/ for showing us this technique and https://www.mayku.me/ for providing the FormBox!
In depth tutorial available in the Sept 2018 edition of Cosplay Culture Magazine! http://cosplayculture.com/
Materials:
Monster Makers dental Alginate/ standard Alginate
Monster Makers Tooth Polymer
Dental impression trays
Ultracal 30
Foam Board
Glue gun
Cups for mixing
Mayku FormBox
Plastic cast Sheets
Scissors/utility knife
Sculpting/dental tools
Dremel
Monster Clay
99% alcohol
Alcohol activated acrylic paint
Acrylic gloss