There were many ROO texts created in the time of Rassilon, the acronym R.O.O. referring to the triumvirate of Rassilon, Omega and the Other. (PROSE: Goth Opera) They were known as Elder Books of the Dark Time. The writings they contained were based upon rituals of the Gods of Ragnarok and the Eternals. They contained rites and incantations which could aid in summoning Chronovores, though they did not always prove easy to control. (PROSE: No Future)