The Seedle Warriors, or Seedle warriors, were brutal psychopaths who took enormous pleasure in killing.
The High Council of Time Lords, for "the first and last time in the history of Gallifrey," dispatched an execution squad after the Time Lord Azmael, with the choice of assassins being Seedle Warriors.
When the squad tracked him to Vitrol Minor, they set about eliminating the populace while Azmael was smuggled off-world, justifying the genocide as the elimination of witnesses to the destruction of a Time Lord. They spent three days murdering before they finally noticed on the fourth day that Azmael had escaped.
When Azmael confronted the High Council about interfering with other planets, the Council was able to bribe their way out of it, creating evidence that Azmael had hired the Seedle warriors to eliminate the population for Vitrol Minor's mineral wealth, even though it had none. (PROSE: The Twin Dilemma)