Ksiistsikomm, Thunder — the Thunderbird — is the storm-power who lives in the mountains and returns each spring with the rain that makes all things grow. In Grinnell's 'Origin of the Medicine Pipe' he carries off a man's wife and is defeated only through the power of the Raven, the one being he cannot kill; in surrender he gives mankind the first Medicine Pipe, the highest of the Blackfoot ceremonial bundles, with the charge to fill and pray over it when he comes in the spring.