If you happen to see a family of four dressed as video game characters or superheroes running down the sidewalks of Mill Avenue in Tempe, don't panic. The Arizona heat hasn't finally gotten to you. They likely are part of one of the off-kilter Urban Dare adventure races. Inspired by such reality TV competitions as The Amazing Race and offering cash prizes and free airfare, these twice-yearly costumed scavenger hunts require participants to don outlandish outfits and dash around Tempe and Phoenix. Meanwhile, they hunt for clues and complete a series of goofy challenges, like maybe a giant game of Jenga or jump-rope contest. Then again, they could just be a bunch of nutters who let the Arizona heat get to them. The next Valley event is scheduled for March 24, 2012.