Celebrate the Batman: Arkham City video game with this totally awesome mug! This Batman Arkham City Harley Quinn Morphing Mug starts out black, but then Harley Quinn is revealed when the mug heats up! This great 11 oz. mug transforms from black as hot liquid is added. Watch as the heat-activated process reveals the hidden image in full vivid colors. Do not microwave. Hand wash only. Not dishwasher safe. Ages 13 and up.