Attempt
The First Doctor graduated from Time Lord Academy by scraping through with 51% on his second attempt. (TV: The Ribos Operation [+]Loading...["The Ribos Operation (TV story)"])
Prior to the first Nestene invasion, the Brigadier noted that there had been two attempts to invade the Earth since the formation of UNIT, and that both were stopped with the assistance of the Doctor. (TV: Spearhead from Space [+]Loading...["Spearhead from Space (TV story)"])
A "fleet of Alien Monsters" once attempted to destroy the Earth, with Doctor Who gathering the "Legendary Legion" in hopes of averting this fate. (GAME: Doctor Who Trump Card Game [+]Loading...["Doctor Who Trump Card Game (game)"])
During the 3W Institute Affair, Kate Stewart presented a damaged Cyber-helmet left behind from a previous invasion "attempt" to counter the claim of a 3W Cyberman that human weaponry was not effective against Cyber-technology. (TV: Death in Heaven [+]Loading...["Death in Heaven (TV story)"])