Planet (Revolutions of Terror)
From Tardis Wiki, the free Doctor Who reference
A planet was home to a reptilian species, which created Cerebravores to achieve a victory in a local conflict.
This species, called the Fleshkind by their horrifying creations, intended to build a dimensional bridge to ambush their enemies, but instead the bridge connected the planet to Earth, allowing an advance Cerebravore party to travel through it. The Doctor used the same bridge to visit the planet, destroy the bridge and return back to Earth. (COMIC: Revolutions of Terror)