Horde of Travesties

The Horde of Travesties fought in the Last Great Time War. The Tenth Doctor mentioned the Horde of Travesties as one of the horrors that would be released when broke the time-lock on the war, along with the Nightmare Child, the Skaro Degradations and the Army of Meanwhiles and Neverweres led by the Could've Been King. (TV: The End of Time) The War Doctor fought against the Horde of Travesties. (PROSE: A Prologue)

Behind the Scenes
In the non-canon anthology, Seasons of War, the Horde of Travesties is portrayed as a creation of the War Lords during the Last Great Time Time War, who attempts to control countless armies throughout history and send them into battle.