10 Darkest Alternate Timelines In Doctor Who
7. The Trickster's World (The Temptation Of Sarah Jane Smith)
Due to him only appearing in The Sarah Jane Adventures, the time-meddling Trickster is a villain that doesn't get as much attention as he deserves.
He's incredibly powerful and deliciously devious, and his cunning nature was on full display in The Temptation Of Sarah Jane Smith, where he created an alternate timeline in which the Earth was reduced to a wasteland.
The Trickster was able to do this when Sarah Jane altered a past event: namely, she prevented the deaths of her mother and father. This essentially "broke" time, allowing the Trickster to move in and manipulate reality however he pleased.
In the Trickster's World, the vast majority of humans are dead, and the few remaining survivors have been enslaved. London has been completely destroyed, and it's safe to assume that most countries and cities have been left in a similar state.
Much like Rose Tyler accepting her father's death in the Doctor Who episode Father's Day, the Trickster's World is eliminated when Sarah Jane accepts her parents' deaths, and the original timeline, thankfully, is restored.