Vengeance of the Vardans

Vengeance of the Vardans was a computer game that Ace wrote in the future as a clue for herself and the Doctor in 1976 to warn them of the Vardan invasion of Earth. The Monk interfered with the timeline, however, and so she never wrote it and the game never existed. Knowledge of the original timeline still existed on a videotape owned by the Monk. (PROSE: No Future)