I was standing on top of an enormous Aztec pyramid. It must have been twenty stories high and its base was massive. A wide row of steps cut through the tiers like an arrow shooting straight for me. Looking down that long stairway left me feeling a little dizzy. As if one wrong step would leave me tumbling forever. I blinked and the feeling was gone.

The doorway of a dark temple arched above me while the temple itself stretched out behind me to cover the pyramid's tip. From my ...