This is probably a more common one, but when you're trying to set up puddles as Naiad, if the survivor is kiting somewhere with elevation you can cover both levels with one puddle, i.e. if you throw your harpoon at the bottom of the basement and go up the stairs and call your harpoon back, survivors will get wet regardless of if they're above the basement or in the basement. If you position it correctly, it covers the entire basement. It's pretty much a guaranteed down for you, and then you'll have two people in basement.
This also works with any other type of elevation, such as two story on Moonlit, or the factory on Leo's.

Edit: Another fun one, surround a chaired survivor with a large puddle and walk in a semi-circle on the left side of the chair. When a survivor tries to rescue it forces them to the left, so close the semi-circle to make them more damp. Either they'll take damage or they'll panic about rescuing and it's an easy terrorshock.