In Greek beliefs, the figure who serves as a guide to the souls in the underworld is Charon. He is depicted as the ferryman who transports the souls of the deceased across the River Styx to the realm of the dead, provided they can pay him with an obol, an ancient coin. Charon's role highlights the significance of proper burial rites and the belief in an afterlife. He embodies the transition from life to death, serving as a crucial figure in the mythology surrounding mortality and the afterlife.