1998 · 替代规则（核心规则变体）
Fathoms: Aquatic Adventures
A fan-created sourcebook for running campaigns set entirely underwater. The downloadable PDF collection includes rules for aquatic races, classes, proficiencies, equipment, adventuring, magic, and the UnderDeep, along with an introduction. A foreword and a separate catalog of underwater creatures are provided in HTML.
资料书（用于增强玩法的规则/选项）等级制（获得经验值并升级）职业制（飞行员、巫师、科学家等）基于种族（玩家的种族/物种影响游戏玩法）
免费，支持网页、Android 和 iOS
用 Ludoya 玩 Fathoms: Aquatic Adventures
游戏信息（人数、游戏时长、年龄、制作人员）来自 BoardGameGeek。