My eight year old son's Hellboy costume I built for him from yoga mats and furniture foam. It started as a Right Hand of Doom project but turned into a full Hellboy project. The hand is fully articulated with pulleys to work the thumb and three fingers independently. I painted it with liquid latex to seal the furniture foam and homemade pax paint to paint the whole thing. The head piece was made by painting a balloon with liquid latex and cutting up a cheap wig.