It’s based on a product for kids but with tweaks to the recipe that make it better for modelling things like armor-and it weighs a lot less than fibreglass. For all you DC Comics fans out there, we’ve got awesome hero costumes like Superman, Batman, Flash, fortnite costumes and more. After giving up on fibreglass but before discovering foam clay, Hu used a thermoplastic called Worbla, which can be shaped when it’s heated.