Homer uses the trope of clouds of mist rendering a god or person unseen (even to people right next to them, in the daylight) a number of times throughout the Iliad and Odyssey. For example, in the Iliad this is performed by Minerva in Book I, Venus in Book III, and at least four different gods in Book V. Minerva does it again in Odyssey Book VII, when she hides Odysseus with a "thick cloud of darkness" that lets him wander through the city of the Phaeacians undetected.
I'm wondering if there are other examples of this trope (invisibility as clouds) in other mythological sources? I have a sense of having seen a similar example in Sumerian or Babylonian works, but I can't put my finger on it anymore. I've scanned all through my copy of Innana and other online sources to no avail. Are there other examples?