The phrase "mere hyperbole" can be replaced with several words that describe exaggerated language or statements. Some possible synonyms for hyperbole include exaggeration, embellishment, overstatement, or extravagance. Other options could be overblown rhetoric, magnification, amplification, or aggrandizement. When trying to convey the idea of language that goes beyond truthfulness, words such as hyperbolizing, inflating, or stretching the truth may also be useful. Ultimately, the choice of synonym may depend on the specific context in which the phrase "mere hyperbole" is being used, as well as the tone or purpose of the message.