2008 · 资料书（用于增强玩法的规则/选项）
Secrets of the Surface World
This sourcebook expands Hollow Earth Expedition with adventures set in the mysterious and perilous surface world, where criminals, mad scientists, dark sorcerers, secret societies, and world powers compete for control of the Hollow Earth. Characters can take the roles of daredevil pilots, private detectives, or wandering heroes as they explore exotic locations and disrupt dangerous schemes. It includes rules for psychic powers, sorcery, and weird science, along with expanded vehicles and equipment, new surface-world locations, and additional details on secret societies.
- 人数
- 0
基于点数（分配点数以获得技能、能力等）基于属性/数值（STR、CON、PER 等）技能型（购买或获得技能）
免费，支持网页、Android 和 iOS
用 Ludoya 玩 Secrets of the Surface World
游戏信息（人数、游戏时长、年龄、制作人员）来自 BoardGameGeek。