Do the Dew
From Twilight Heroes Wiki
You take off straight up into the air and set your sights on one particular cloud that seems to be calling to you. As you fly into its center, the mist around you seems particularly dense. Curious, you set your flying machine on autopilot, extend a plastic bottle into the mist, and fly around for a while. When you retract the container, it's half full of the purest, cleanest, refreshingest water you've ever tasted.
You got an item: sky water
Found in the flying above Twilight area.