An incredible piece, of what some believe to be, technology. It is primarily theoretical as practically no one has much use for one and even fewer can create one.
It generally takes the form of a churning mass of black/green smoke in the middle of an arc.
It is Alternate Space, within which a simulation is being carried out. A mixture of nano tech and life force manipulation, it represents all possible forms of life that can exist in a galaxy, no a universe. With it, someone can create any life form they like, become any life form, that exists within 3-D space or give life to an entire world.