Senecca B
Senecca B was a small distant planet, in a red sky part of a galaxy heavily populated by nearby planets and moons, that is mostly covered in vegetation and swampland. The indigenous life form underwent an evolutionary change over their life cycle that saw them get rid of all their negative emotions through a metamorphosis. Occasionally the process stalled and all the negative emotions were allowed to grow and the creatures became a predatory and savage, rage filled monster that fed off the others. When the Doctor, Amy Pond and Rory Williams arrived they were able to lure the Venghu (the savage negative form), into a trap and extract all the negative emotions allowing for the more positive creature within to emerge. (DWA: The Rage)