Great Snake
From Tardis Wiki, the free Doctor Who reference
The Great Snake, possibly also known as the Eldest Shadow, (PROSE: Prelude Falls the Shadow) was an entity that breached the walls of Cathedral at some point millions of years before 1994. The Grey Man and the city's citizens, and presumably the Mandelbrot Set, fought a war against the Snake, using huge vehicles that fed on coal. (PROSE: Falls the Shadow)
