The human face is supremely important on a social and biological level. Most of our non-verbal communication comes from reading subtle facial movements, and its importance in our cognitive thinking is best shown in our tendency to see faces in inanimate objects (think of how many times you have looked at a rock face and thought you'd seen two eyes and a mouth). So there is something genuinely disturbing to most people about seeing a face visibly distorted, mutated, or rearranged ... so, naturally, this type of Body Horror is one of the most common Horror Tropes. Sub-Tropes include: