Pepakura-cast Halo helmet
YouTuber utubewarrenj is part of a community of cosplayers that are using a pretty amazing low-tech process to go from digital models to relatively accurate, durable real-world objects. Basically, they print out, fold up, and tape together elaborate paper models (for an idea of how much work this is, check out this video by SeamusRocks99), then fiberglass over and/or cast liquid polymer resin into them to produce durable full-size artifacts, which is what he’s showing here.