Reddit mentions of Adult Unisex Mock Neck Long Sleeve Unitard 8815BLKM Black Medium

Well, let's deconstruct the look a little bit. Here's my guess on how to approach the costume:

• Bodysuit: You need a black form-fitting bodysuit that you can airbrush all the sinew-like ripples onto. Depending on your budget, you can look at buying a unitard like this or sew your own. If you don't have airbrushing tools or can't afford them, you could also carefully sponge grey/silver paint onto the bodysuit, but regardless of application you should make a duct tape dummy of yourself first in order to have some fuller form to paint on. You'll probably need separate black gloves, since most bodysuits don't have built-in gloves.
  
  
• Sleeves: Make sleeves that go to just below your elbow that you can pull up over the body suit to cover your arms, to make that sort of flared look at the wrists. You'll either need to find fabric that blends that way, or find a dark red fabric that you can bleach to get that gradient. If you want to go the bleaching method, /r/bleachshirts can give you tips on technique and safety.
  
  
• Chest: Painted with a brush and fabric or acrylic paint, or even mildly diluted acrylic ink, depending on what effect you're going for.
  
  
• Head: Papier mâché onto a large blown up balloon. Cut out eyeholes and possibly a mouth hole when it dries. Paint the whole thing black, then additionally cover the mask with black fabric that you can see through. That way, the fabric won't show the colour of grey newspaper underneath – it'll all be dark, and with care in construction people might not be able to tell there are even eyeholes. To make the silver trim, I would suggest some decent quality silver cardstock after you've covered the mask in fabric – that way, the cardstock can cover raw edges, and you can easily cut it out after attaching it.
  
  
• Belt+skirt: You can make your own belt out of felt, faux leather, whatever you like. Your best bet might just be to find a few red belts though, and buy 4 suspender buckles. The first red belt can go around your waist, the second you chop up to make the X in the front. Then when you make the skirt, you can permanently attach it to the red belt that goes around your waist. I see the skirt is blue and red, so you might want to make that two layers (blue skirt atop red larger skirt), or one layer (sew blue atop red, or connect them).
  
  
• Boots: Find some cranberry coloured (rain?)boots. Paint the stripes onto the boots. Then carve some medium- or high-density foam with the gear-tooth-like incisions (you can use scissors, an x-acto knife, or best of all, electric carving knife!), cover it with grey fabric, and glue it securely around the base of the boot. If you've picked up rain boots, you can cut the top of them to look like the shape it should be, and then cover the raw edges with dark grey/black foam tube shielding, or just plain black fabric.
  
  
• The weapon?!: Crap, that's hard. That's going to be a lot of patient work with some combination of any of foamboard, papier mâché, a wooden dowel (to go straight through the entire thing and give you max stability), some custom cut chains from the huge selection at Home Depot, and if you can find it, a nice blue baubly fake jewel thing OR the largest cat craft eye you can find, OR half a transparent sphere, opened snow globe, or something. You can even go up to one of those machines that takes 25 cents or a dollar and get a toy from it, toss the toy, keep the round translucent casing it came in. If you end up finding a large transparent half sphere of sorts, paint the black cat pupil FIRST, let it dry, then paint the blue iris overtop. The sphere will make the colours glorious, without having had to paint the round outer part of the sphere at all.
  
  These are just suggestions! Use what's right for you. Epic costume endeavour, good luck on it!