Sen no Kiseki III Confidential Material Book ~Erebonian Empire 1206~ (英雄伝説 閃の軌跡III 秘蔵設定集 ～EREBONIAN EMPIRE 1206～) is a booklet that was included in the limited edition of Ys VIII: Lacrimosa of Dana for PlayStation 4, which was released on May 25, 2017.
- Main/Sub Character Illustrations, p.03-19.
- Key Visual, p.20-23.
- Concept Art Gallery, p.24-25.
- World Visual, p.26-27.
- Weapon/Gadget Design, p.28-29.
- Emblem Design, p.30.