You know your shadow self well and you always have. Your shadow walks with you, a dark reflection, a fellow self.
You reach a building here in the field. The building should be something of your choice. Conjure it up: a barn, a cottage, an abandoned house, a mill or a burned-down castle or a lonely tower.
This is your Sanctuary. It beckons you. It's something special and you know it. You walk up to its front door but, as you are about to cross that threshold, something occurs to you. The shadow is not to come with you. So reach down and grab the shadow by the place it connects to your feet and pluck it off you, tossing it backwards into the field.
It is no longer just a shadow. It is now your Shadow Self.
Now, enter the Sanctuary, and begin to explore.
You are inside the Sanctuary now. It is mostly how you imagined it would be before you arrived but with some differences. Perhaps it's a bit cleaner than you thought it would be. Perhaps a bit more cluttered. Perhaps there are items of great value in here, and if not, do not worry as you still have much time to fill it.
Take a look at the objects throughout the Sanctuary, whether it's one room or a thousand. Explore until you get to know it, but remember that your Shadow Self waits outside and that it grows impatient.
Now you must play a game with your Shadow Self.
Ensure the curtains are drawn, if there are curtains. It not, ensure that your Shadow Self does not see you. Survey the objects again. Know them. Then leave the Sanctuary. Go to the front door and step aside and leave the door open and nod to your Shadow Self. Let it know that its turn has come.
You will wait outside, your Human Self, as your Shadow Self goes in and explores with one simple objective: to steal an object from the Sanctuary. You cannot look in the windows, as your Shadow Self sneaks through the building with the simple purpose of tricking you. It will steal an item but, even moreso, it will rearrange the entirety of the building so that it has become an entirely new place, the same pieces but a new arrangement.
Now, pause for a moment because there is something important to remember in this game: you are both of the selves. You control each. The goal is not to trick the Shadow Self or the Human Self. The goal is to be both at once. To contain multitudes.
Wait for it, outside, your Human Self, while your Shadow Self gets into mischief.
Soon your Shadow Self will come outside again and it is your Human Self's turn to go back into the Sanctuary where you will complete one simple objective, the objective of this entire exercise: find the object the Shadow Self stole.
Go back inside and see what you have done.
Only when you have found what it was — found which object is now missing — because you stole it without letting yourself know this — there in the building you built, can you consider the game complete.