An door appears in the Diamond Gardens. It stands man-high, without walls to support it, or any structure behind it. It is not linked to a particular location, but moves about, sometimes appearing in the Lava Molts, sometimes in the Arboretum or beyond. From time to time, a keen observer can spot the door sidling surreptitiously from place to place on what look very much like chicken legs.
The door is made of a satiny grey substance somewhere between metal and plastic. When approached, it slides open with a hiss of air. Through the door is an expanse of white. The floor is perfectly flat and smooth, shiny and white, with faint blue-grey grid lines at 5 decimeter intervals. In all other directions, there is only a bright white fog. It is impossible to determine the dimensions of the space. It is a blank file, ready to be filled with whatever becomes necessary.