The magi lays out nine cardboard numbered grave markers, explaining that only one of the markers (which are actually little folders) holds the Guardian's coffin. And as we all know, the Guardian must have his coffin to survive. The spectator places the guardian on ANY grave marker, and the magi then turns him on by pressing a button on the Guardian's chest. His eyes flash, and he speaks "Welcome!". Now the spectator pushes the button and again the Guardian speaks, telling the spectator to remove one of the numbered grave markers. The spectator pushes the button again and the Guardian tells her to move him 5 times . Each time she moves the Guardian, she pushes the button, he tells her to remove a grave (by the number), and then tells her to move him some number of times. Never does the Guardian name a grave on which he is standing, so after a while, it becomes clear he is narrowing down to just one. As each grave is eliminated, it is opened to show it contains nothing. After eight eliminations, the Guardian announces which grave he is on, and inside is found a small card depicting his coffin.
So, here are a few key points: the trick can be repeated immediately for the same spectator and the coffin will be in a different grave! The magi never touches the Guardian after it is turned on. The whole thing is self contained -- the magi truly does nothing to influence the effect once it is started -- no remote control, etc. In fact, magi could go away and have a cup of coffee while the spectator lets the Guardian guide her through the effect.