THQ announced it has shipped MX vs. ATV Unleashed: On the Edge, the racing game specially developed for the PSP by Rainbow Studios. Powered by the Rhythm Racing physics engine, MX vs. ATV Unleashed: On the Edge features new tracks and vehicles and 4-player open class ad hoc wireless competition. The Outdoor Freestyle Mode, exclusive to the PSP, offers over 40 rider stunts, and players will battle for off-road supremacy in varied competitions such as SuperMoto, Short track, Hill climbs, and Waypoint races.