2003 · キャンペーン設定（ゲーム世界）

Ghostbusters: Who Ya Gonna Call?

This d20 Modern roleplaying supplement adapts the work of professional ghost hunters, treating ghosts as biological entities that can be studied, contained, and destroyed with specialized equipment. Players create and develop Ghostbusters using new allegiances, occupations, skills, feats, weapons, and equipment such as proton packs and ghost traps. The supplement also introduces an elite Ghostbuster advanced class, action point rules, planar travel, and a classification system for supernatural creatures.