In the Epic of Gilgamesh, a serpent steals the Plant of Rejuvenation from Gilgamesh.
After retrieving the plant from the bottom of the sea, Gilgamesh stops to bathe in a pool. A serpent detects the plant’s scent, takes it, and then sheds its skin. The image explains why snakes became associated with renewal: their shedding resembles the casting off of an old body.
The episode is a final reversal in Gilgamesh’s quest. He has learned that Utnapishtim’s immortality cannot be transferred to him, and the plant offers only renewed youth. Its loss makes the limits of human life unavoidable.
The serpent is not named as a particular divine monster in the standard narrative. It is simply the animal that takes the plant. This detail is sometimes linked loosely with later serpent symbolism, but the epic itself gives the scene its own Mesopotamian context.