GUDANNA
Ancient Sumerian Mythology
This is the name of a monstrous bull in the mythology of ancient Sumer. GUDANNA was described as a vast creature with such poisonous breath that it was capable of killing over two hundred warriors at a time. It was created by the great god ANU at the behest of the goddess ISHTAR to wreak vengeance on the hero GILGAMESH for refusing her advances. GILGAMESH, with the help of his friend ENKIDU, managed to slaughter and dismember GUDANNA. This so enraged the god that ERKIDU was slain in revenge.
Source: Giants, Monsters, and Dragons: An Encyclopedia of Folklore, Legend, and Myth