The iconic Psycho Bandit from Borderlands was my first video game mask replica. I love those little stitching details and that disturbing fan mouth.
I knew I wanted a sturdy, wearable mask in the end, so I decided up front that I would be molding the original sculpt so I could cast copies from urethane resin. This means I didn't really need to worry about my sculpt being not-so-robust.
I started with a Pepakura paper model. I coated this with some fiberglass resin to give it some strength, then cut out the eyes and the mouth. I'll be sculpting the mouth separately and adding that back in later. To smooth out the Pepakura polygon edges a little, I added a layer of Bondo over the top of the mask and then sanded it down.
Over the top of the Bondo I added a layer of Apoxie Sculpt self-hardening clay. This is the material I decided to use for the base surface of the mask. With this first layer of Apoxie Sculpt, I smoothed out any remaining Pepakura edges and sculpted the structures for the eyebrows and the ridges around the eye openings.
After sanding down the Apoxie Sculpt base to remove most of the texture, I had a smooth surface for adding the strips of stitching. I used Worbla thermoplastic for the strips, cut using templates I created from a second Pepakura model. I probably could have just shaped these free-hand, but I wanted to get as close to the in-game model as possible. Worbla was also used for the outside edge of the mask.
The mouth fan was constructed using an actual PC fan as a starting point. I removed the fan blade portion from its original housing and lodged it inside a short bit of PVC pipe. To make it easier to mold and cast, I filled in the bottom sides of the fan blades with Apoxie Sculpt. The raised "heat sink" ridges on the center of the fan were cut from an old credit card and glued in place. I then tacked the mouth fan assembly in place with some hot glue so I could sculpt around it with more Apoxie Sculpt.
For the stitches, I cut short little bits of insulated wire, bent them into a slightly curved shape, and then pressed them into the Worbla. This has a pretty convincing effect. They look like they're stitched all the way through the mask, but they're really only on the surface. For the final, gritty texture of the mask, I added another thin layer of Apoxie Sculpt. I pressed an old towel into it while it was still soft in order to give it that pocked texture. For the little bolt heads on the chin, I sliced off the tops of some googly eyes and glued them in place with some superglue.