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The Festival of Death was a carnival held on the G-Lock. According to Harken, it was a carnival "that attract[ed] thrill-seekers and tourists from throughout the galaxy like a big magnet". It celebrated the act of dying. The central attraction of the carnival was the Beautiful Death, a "trip" that essentially allowed the user to die for half an hour and experience the afterlife.
The Fourth Doctor, Romana II and K9 Mark II once went to the Festival of Death, where the final Beautiful Death was "hi-jacked" by the powerful being known as the Repulsion, a being of pure death, whose realm had been accessed by past users of the Beautiful Death; all but one of the 218 participants were reanimated as the living dead until the Doctor destroyed the Repulsion. (PROSE: Festival of Death)