It's written on p. 278 of Grandmaster Chen's Training Records, that "There wasn't a single candle in the Dark Kung Fu Pet's habitat, yet the Dark Kung Fu Pets were walking around freely as if it were daytime."
The Huge Dark Habitat is truly a strange place. The building's walls are visable when you're outside but once the door closes, no one can see where the walls are. You'll be lost inside the building until someone else comes to open the door for you!
