Well, for me, at least, the word 'mudlick' came out of a book called The Darkangel, by Meredith Ann Pierce. (And I knew a girl by that name once, but not the one that wrote the book.) In this book there's an evil lorelei/water witch who lives in a still dead black pond. When one woman drinks from this pond, a mudlick rises from the water to speak to her. It was a small, colorless creature, if I remember correctly. A servant of the lorelei who convinces this woman to bring a little boy to this pond and drown him there. Not really the most sympathetic of characters.

But that's not the way I use it now. To me, a mudlick is a sort of faerie creature - one that has no wings and isn't particularly attractive, and lives in places like swamps or the bottoms of ponds or wet caves (or under rocks, as long as it's damp). Dark, dank, and dreary - but not necessarily evil. Generally misunderstood. Mudlicks should get along nicely with marshwiggles.

To be super-geeky and put it all in Changeling terms, the Mudlick kith is a cross of the Sluagh, the Water Baby, and the Yunwi'amai'yine'hi (if I spelled that right). They can have the advantages and disadvantages of any of those kiths, but do not get Cantrips. (Frex, Snake-In-The-Grass, my old mudlick character, was like a Sluagh - she spoke in whispers, she could Squirm, and she had a very long tongue (merit from the Sluagh kithbook). She was also scaly and could transform into a salamander-like thing while submerged in water (and risk the same penalties as one of the yunwi'...). And she had the Water Baby's feelings for children and desperate need to stay wet. But aside from the ability to step sideways when in contact with natural water (totemic, sorta) she had no Arts or whatever those Cantrippy things are.)

Oh, were you looking for personal information? Sorry, nope. I'll give you this much - I don't look like that picture. (Doodled in PC Paintbrush.)