This work is dedicated to the analysis of two types of discourse found in caves: the prayers recited today by ritual specialists, and the hieroglyphic narratives recorded by ancient scribes. To this end, the book compiles and systematizes the cave prayers published to date and also presents an updated Spanish translation of the hieroglyphic inscriptions found in certain caves, primarily in Naj Tunich, Guatemala. The study thus seeks to provide the necessary elements to distinguish and appreciate an ancient, unique, and formal language of the underworld.