There has been more written about Enki than any other Sumero-Akkadian deity. The importance of water in a partiualrly arid climaate may explain why Enki, the water-god, played such a prominent role in the creation myths of Sumer (Kramer & Maier). In addition to being the water-god, Enki was the god of wisdom and craftiness. It's possible that wisdom and craftiness spawned from his designation as water-god. The building of irrigation cannals on the otherwise arid plains of southern Mesopotamia are what allowed Sumer to bourgen into humankind's first known urban civilization. For this very reason, it is possible that water was associated with the genius of harnessing it -- through the use of irrigation -- thus the supreme god of water would also be envisioned as wise and crafty. This is all Speculation, of course, but we do know Enki's popularity did not wane with the deterioration of his home city-state, Eridu:  Enki was tied very closely to an ecological niche and the economy of the marshes in southermost Iraq. When Mesopotamian civilization moved inexorably north into a different ecological condition, Enk's role in some ways diminished, and eridu became a sacred city, a pigrimage stop, instead of the political and economic center it had been before. the fertile valleys of northern Iraq, the heartland of the Assyrians, had sufficient rainfall for crops and pasturage. The yield eve today is greater there than in the alluvial plains of the south. What did not diminish in the movement of Mesopotamian civilization was the reliance on magic. Indeed, magic seems to have become more and more important through the second and first millennia. That meant the role of the esoteric Enki would remain long after his cult city had lost its political importance. (Kramer & Maier)

In this impression from a cylinder seal, Enki is easily identifyed as the god (wearing a horned crown) with streams flowing from his shoulders. He is seated on a thrown, presumably in judgment of a bird-man. Possibly the Anzu-bird that stole the divine me from Enlil?