From the PDF introduction
A Web Enhancement for Fiendish Codex II: Tyrants of the Nine Hells
Fiendish Codex II: Tyrants of the Nine Hells is packed to the brim with information about the Nine Hells, devils, archdevils, harvesting souls, playing devils, and more. If you like using devils in your campaigns, you should get this book to help you flesh them out. It also includes updated versions of devils that saw publication in Book of Vile Darkness and the different Monster Manual tomes. At the end of the book you’ll find aspects of the archdukes, the rulers of the layers of the Nine Hells. The aspects of the Lords of the Nine presented there are suitable for high-level campaigns. However, you might want your lower level player characters (PCs) to encounter appropriately challenging aspects of the Lords of the Nine. This web enhancement presents these mid-level aspects, along with a revised aspect of Tiamat (originally from Miniatures Handbook) and aspects of the kobold deity Kurtulmak and the sahuagin deity Sekolah.
As with the demonic aspects in Fiendish Aspects I, you can create different "versions" of the aspects than those presented here. Each archduke is complex and has many powers. If you want a version along different lines, just swap out the special abilities for the ones you want, using the high-level aspects presented in Fiendish Codex II: Tyrants of the Nine Hells as your template.
Since the Nine Hells are very orderly, the aspects are presented in order of planar home from first to
This document shares the same name as the 2nd web enhancement for Fiendish Codex I: Hordes of the Abyss. Fiendish Aspects II