Giant Torayan, a huge aluminum robot, looks down on a puny human at the lobby of the Osaka City Hall. The robot, a statuesque 7.2 meters tall, responds only to instructions from children, according to its creator, Osaka native Kenji Yanobe. When feeling chipper, the robot can sing and make simple dance movements. But do not anger Giant Torayan: It spews fire when miffed. The robot's job is to promote Aqua Metropolis Osaka 2009, an event highlighting the city's water-related attractions that starts Saturday.