This originally went with a story about a planetary guardian. The colossus is worshiped by desert nomads as the god Obu. Little do they know that he's a complete figure. His purpose is to guard against threats from space. The rub is how to activate him, since that has been lost for millennia. As dragons fly overhead on a routine operation, a wizardress tries to raise the colossus, but finds she doesn't have the moxie. There's a Viking sorceress who does, and the story details the quest to bring her onto the scene--in time to stop a planet-killing space station.