Secrets of the Surface World, hardback sourcebook for Hollow Earth Expedition
“The first sourcebook for Hollow Earth Expedition contains everything you need to run thrilling surface world adventures or add more spice to your existing Hollow Earth games.
This sourcebook contains:
• New rules for psychic powers, sorcery, and weird science.
• Expanded vehicle and equipment catalog.
• Expanded secret societies information.
• Additional details on surface world locations.”