The Toymaker (Barusa's universe)
In one of the infinite parallel universes of "possible space", (COMIC: Fire and Brimstone) the Doctor once encountered the Toymaker in 2525. He was an "evil force" controlling a "fantasy world". After rendering the TARDIS inoperable, the Toymaker challenged the Doctor to a deadly mind game which, if lost, would have resulted in eternal imprisonment for the Doctor. As Barusa discovered, however, the Toymaker was under the control of the Doctor's own half-brother and archnemesis, the Master, who had set up the mind-duel in an effort to get rid of the Doctor once and for all without any blood on his own hands. (PROSE: The Chronicles of Doctor Who?)