Andric

 served under the Craxon Supreme Commander, Zusa. He met the Fourth Doctor when the Time Lords directed the TARDIS to the Craxon crown ship. Zusa offered Andric as a reliable assistant for the task of finding a new source of Diloona, the ore which powered Craxon spacecraft.

He travelled with the Doctor to an artificial "planet" — in reality a satellite — that was manufactured by the Mangans as a proving ground for their young. Together, they faced a number of dangers before coming to an accommodation with the Mangans. (TVC: The False Planet)

Behind the scenes

 * Andric occupies the narrative space of a companion. Not only is he the one asking the Doctor all the questions the audience wants to know, but he takes a couple of trips in the TARDIS during the course of The False Planet.  The story even ends on an "interior TARDIS" scene of him handing the Doctor the sonic screwdriver.  The fact that the story ends with the Craxon still on board the TARDIS makes it possible to believe he could have gone on other adventures with the Doctor.