2003 · 资料书（用于增强玩法的规则/选项）
Underdark Adventure Guide
A world-neutral guide to the Underdark, an underground realm of civilizations, ancient ruins, sunless seas, strange magic, and dangerous creatures. It provides character options, equipment, monsters, plants, and fungi, along with advice for building an underground region and a dozen developed locations. The locations can be used separately in an existing campaign or combined into a larger setting.
技能型（购买或获得技能）基于属性/数值（STR、CON、PER 等）等级制（获得经验值并升级）
免费，支持网页、Android 和 iOS
用 Ludoya 玩 Underdark Adventure Guide
游戏信息（人数、游戏时长、年龄、制作人员）来自 BoardGameGeek。