The Seven-headed Serpent (from Sumerian muš-saĝ-7: snake with seven heads) in Sumerian mythology was one of the Heroes slain by Ninurta, patron god of Lagash, in ancient Iraq. Its body was hung on the "shining cross-beam" of Ninurta's chariot (lines 55-63 [1]).
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Seven-headed serpent Wikipedia(Text) CC BY-SA