  The Canterlot gardens had no idea what was about to hit them. The air nearly crackled with magical potential in the bright afternoon sun as a circle of a dozen unicorns, horns glowing, surrounded a bare patch of grass. In the center of the circle stood Princess Luna, her horn glowing and wings half-spread as she frowned in concentration. Twilight Sparkle, blinking furiously to keep the sweat out of her eyes, carefully matched her output to the other unicorns around her. 