Nebula

Not to be mistaken for your average, run-of-the-mill nebula, oh, no, this is a sentient nebula, an example of which we encountered in “The Daleks’ Master Plan”. That Nebula in particular was Celation, a member of the Galactic Council collaborating with the Daleks.
Podcast C021 The Daleks’ Master Plan > > > > > > > > > > > > > > > > >

The Doctor robs the Daleks, gains two companions, loses three, and then we even get an appearance by the monk. Epic!
Podcast C019 Mission to the Unknown > > > > > > > > > >

Three astronauts who aren’t The Doctor battle homicidal vegetables and Daleks while the latter plot to take over the galaxy.