Per the thread on the (highly likely) hoax game Stop, might a template to display at the top of articles that are potentially a hoax be a good idea? It hurts the site's credibility to have entries with no reliable evidence of existence, and while "Existence unconfirmed" exists, I believe that's supposed to be for things that are rumoured by reliable sources, not just anything somebody adds to the site without sourcing. A hoax template (similar to the NSFL one, maybe) could be added to any such articles not obvious enough to delete outright, but which are disputed, and would make it very clear to any reader immediately that the contents should be taken with a grain of salt.