A Call of Cthulhu comic with a rumor that could be adapted for UA.
This is one story in a larger CoC volume. Tweak the nature of the beastie, and you have something perfect for UA.
http://webcomics.boom-studios.net/2008/11/13/cthulhu-tales-vol-1-page-64/
The rest of the comic is worth reading, but none of it is nearly as adaptable for UA.
That’s awesome. I will definitely be using that.