The Seven Holy Rituals were a religious practice of the Swampies. They were seven different punishments exacted to cause death to an individual in sacrifice to Kroll. The Fourth Doctor, Romana and Rohm-Dutt were sentenced to die by the seventh holy ritual of the old book. This involved being tied with vines, known as creepers, that tightened under the sun. They would stretch the victim until the spinal column broke, causing death. When it rained, these creepers slackened and the trio escaped. (TV: The Power of Kroll)