Chylbyga is the eclipse-monster of the Tuvans, imagined as a shaggy old hag or a many-headed dragon-serpent who devours the Moon during a lunar eclipse and the Sun during a solar one, so that people once beat on iron and copper to frighten her into disgorging the light. An aetiological myth explains her enmity: when a creator-deity was distilling the water of immortality, Chylbyga stole and swallowed it and fled into the sky; the Moon betrayed her hiding place, and in revenge she swallowed the Moon, whereupon the creator overtook her with his scepter, the ochur-baanai, and cut her to pieces to free the luminary. She belongs to one of the oldest strata of Turkic folklore, appearing across Siberia and Central Asia under cognate names such as the Altai Dʹelbege and the Kyrgyz Zhelmoguz-Kempir.