For one reason or another (mostly me having to take an extended break from working) we never released all of the books we had planned, but one thing we did put out was Whispering Darkness, an adventure Matt wrote that takes place deep in the mines under Shadepoint (or any other location of your choosing).
I really love this adventure. The monster Matt created for it is supremely creepy, and the artwork we commissioned is some of my favourite art in any book we’ve put out.
As of today, Whispering Darkness is Pay What You Want on DriveThruRPG. Go pick up a copy and keep it in your GM folder for when you need a quick, creepy sidequest to drop into your game. Go grab a copy!