1. Cthonic: Relating to the underdark. Gharsh Lighting: The Art of Illuminating Dark Places
2. Labyrinthine: Describing a complex, confusing, or bewildering experience or structure. Mnemonics of the Mind: A Guide to Remembering Your Way Out
3. Subsolar: Relating to the hidden areas of the sun. Solar Sleuths: Uncovering the Hides of the Sun
4. Tenebrous: Dark and mysterious, like a cave. Cavernous Communications: The Art of Whispering in the Dark
5. Gnarly: Describing something twisted or irregular in shape. Geomancers: The Twisted Art of Shaping the Land