2004 · ソースブック（プレイを拡張するルール／オプション）

Blood and Circuits

This d20 roleplaying supplement focuses on characters who design, build, and use advanced technology. It introduces new advanced classes, feats, expanded skills, and combat options for inventors, engineers, armorers, gadgeteers, and other technically minded heroes. An optional crafting system uses Invention Points to create weapons, armor, computers, vehicles, robots, headquarters, and other equipment. Additional material supports strange scientific achievements and includes appendices for Blood and Vigilance and Darwin’s World Second Edition.