The umbrella prop has already been suggested before. And to make that umbrella prop appear flawlessly, I think it would be great if there is an animation where a character actually holds an umbrella. Here are some animations that come to my mind:
idle_umbrella_closed_neutral (the character is holding a closed umbrella)
open_umbrella (the character opens a closed umbrella)
These animations would be great to use in dramatic rainy scenes. Not only in rainy scenes, but also in scorching sunny scenes.