I'm going to Zenkaikon in a week or so, so I was just gonna ask, will craft foam work? (for the mask that is) Because I heard you can melt it and shape it to your liking
I suppose craft foam would work. I assume you are meaning the skull-like chin portion. You could probably heat-form the craft foam, although you'd need to probably reinforce it and seal/paint it to get rid of that soft foam texture. A few coats of school glue after you've formed it and you should be able to paint it smooth.
Wonderflex. You can get a 3x5 sample of it, and it was just enough to heat and mold onto the chin of a mannequin head. Trimmed off the corners of the wonderflex and used the scraps for the teeth. Silver acrylic mixed with black for that gunmetal look, sharpie for the details.