"Many strange things may be seen in the Great Swamps, not all real. But I tell you, there was a ship and it was real! Well it was old and all sails torn and had many holes in the hull... but anyway it was hundreds of miles from the Sea! How it came to be there, I can only wonder..."
(If it is not a hallucination, may be inhabited by wererats.)
Serpens Necto is a mask made of snake skins stitched together and crudely painted in white. With this on a person can bind people to their will under the right conditions. In darkness the effect of the mask is greatly enchanced by illumination from under by a candle.