Cook did just that, stepping up the mirror's dais and extending an arm to press his booted hoof against its surface. A magenta swirl of light faded in, displacing their reflections. He stepped back again and, with a toss of his head, flung his burden at the portal, letting his levitation lapse at the last moment. The paper-wrapped stone vanished and the mirror once more reverted to a disarming quiescence.