2004 · 替代规则（核心规则变体）
Modern d20 Core Kit
A modern d20 roleplaying rules kit for contemporary campaigns without supernatural or science-fiction elements. It includes the d20 Modern System Reference Document, expanded character-creation rules covering base and advanced classes, feats, and skills, plus a modern d20 character sheet.
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 Modern d20 Core Kit
游戏信息（人数、游戏时长、年龄、制作人员）来自 BoardGameGeek。