Fictional worlds often have problems. Many of these issues arise because of how fantastic elements are incorporated into the setting. Certain elements may not be realistic for the setting, or may not match the genre or tone, or may raise questions, conundrums, or paradoxes to which the worldbuilder does not have an answer. However, fictional worlds are fantasies meant to entertain and often the ‘cool factor’ of an element far outweighs the need for realism or internal consistency. The ‘Rule of Cool,’ or the idea that it’s okay to sacrifice some believability if something is entertaining enough, can be used to mask certain worldbuilding problems. Take for instance the problem with giant battle mechs. Massive bipedal robots may not be a very realistic combat force – they represent large targets, they can be outmaneuvered by rocket-carrying infantry or drones, and their plethora of articulating parts always under enemy fire represents a smorgasbord of areas where things can break and systems fail. However, for fans of giant battle mechs the ‘rule of cool’ far outweighs the need to develop a robust explanation for why giant robots are used in battle. Sure, additional solutions can help make giant robots more reasonable within the context of a world (their use may just be a cultural thing) but who are we really kidding? Giant robots are just pretty cool and just that obvious one fact may be enough for audiences to accept them without further thought.