• The Fourth Doctor helped human scientists kill the last of the Pescaton by the application of high-frequency sound waves. The Pescatons had fled their dying homeworld in search of another planet with large areas of salt water that could support them. (AUDIO: Doctor Who and the Pescatons)
• The Fourth Doctor destroyed Sutekh, the last known Osirian. He even taunted Sutekh as he died in the “temporal trap”, asking him how long Osirians live, before finally declaring “The time of the Osirans is long past. Go.” (TV: Pyramids of Mars) The Fifth Doctor would encounter further Osirians (PROSE: The Sands of Time, AUDIO: The Bride of Peladon), but would be forced to destroy them as well.
• The Fourth Doctor killed Eldrad, the last Kastrian (TV: The Hand of Fear) He would later encounter another surviving Kastrian, Mulkris, assigned to ensure that Eldrad’s sentence was carried out (AUDIO: Eldrad Must Die!).
• With Leela’s help, the Fourth Doctor destroyed the last of the Fendahl. He dropped the remains of the Fendahl into a supernova to ensure their permanent destruction. (TV: Image of the Fendahl) However, this attempt appeared to have failed, as the Fendahl later managed to re-manifest in Kaldor City (AUDIO: Checkmate), and it was later revealed that the Fendahl defeated here was only a fragment of the true Fendahl that remained trapped on Planet 5 (Although the true Fendahl was consumed by the Fendahl Predator) (PROSE: The Taking of Planet 5).
• The Fourth Doctor fulfilled a Time Lord’s solemn duty by killing the King Vampire, the last of the Great Vampires and sole vampire survivor of the Vampire-Time Lord war. (TV: State of Decay)
• When the Sixth Doctor was forced to wipe out the Vervoids to stop them killing the humans on Hyperion III, this was used against him in a Trial occurring in his own past. When the Valeyard accused the Doctor of genocide, the Doctor said that he had no other option. (TV: Terror of the Vervoids) When the Eighth Doctor travelled to the events of the trial and met his sixth incarnation, he dismissed the charge due to the artificial nature of the Vervoids’ creation. (PROSE: The Eight Doctors) (However, the Tenth Doctor was shocked by the destruction of the Dalek-humans, another artificially-created species (TV: Evolution of the Daleks))
• The War Doctor committed double genocide when he destroyed the Time Lords and most of the Daleks at the end of the Last Great Time War in an alternate timeline. It was apparently Rassilon’s Ultimate Sanction, which threatened the whole universe, that convinced him he had no other choice. (TV: The End of Time) With the help of the Tenth and Eleventh Doctors, he found a different solution and with the help of every past and future incarnation of himself, froze Gallifrey and the Time Lords in a pocket universe while the Daleks destroyed themselves. (TV: The Day of the Doctor)
• During the Dark Times, the Fledgling Empires all but wiped out the Racnoss to prevent their devouring of planets. The Tenth Doctor later made them extinct when he flooded a ship of surviving young within the Earth. He was unknowingly aided by the Master, who ordered the destruction of the Webstar which resulted in the death of the Empress of the Racnoss. (TV: The Runaway Bride)
• The Doctor accused his Meta-Crisis duplicate of genocide when he destroyed all the Daleks in the Medusa Cascade, along with their fleet and the Crucible. As he thought he was too dangerous to be left to his own devices, he left him in Pete’s World with Rose Tyler so she could make him better as she did for the Ninth Doctor himself. (TV: Journey’s End) It was later revealed that at least one Dalek Saucer, with three surviving Daleks on board, managed to escape, and they were able to rebuild their race using Progenitors. (TV: Victory of the Daleks)
• The Saturnyns were wiped out, with the Eleventh Doctor’s help, in their attempt to take over Earth and convert female humans into new mates for their males. The converts were killed in an explosion, leaving the males to die out. The last female, Rosanna Calvierri, offered herself as a last meal to them, after telling the Doctor she hoped that their extinction would haunt his conscience. (TV: The Vampires of Venice)
• The Twelfth Doctor destroyed Rann-Korr, the last Hyperion by channelling seas to his caverns. (COMIC: Terrorformer)

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