The Teton texts of Bushotter state the belief that “some of these ancient people still dwell in the clouds. They have large curved beaks resembling bison humps, their voices are loud, they do not open their eyes except when they make lightning, hence the archaic Teton name for the lightning, Wakinyan tunwanpi, “The thunder-beings open their eyes.” They are armed with arrows and “maza wakan” or “mysterious irons” (not “guns”), the latter being of different kinds. Kaŋġitame, stones resembling coal, are found in the Bad Lands, and they are said to be the missiles of the Thunderers. When these gods so desire they kill various mysterious beings and objects, as well as human beings that are mysterious. Their ancient foes were the giant rattlesnakes and the prehistoric water monsters

A Study of Siouan Cults, p. 442