Shadows of a Dying World is a d20 RPG supplement produced by Skirmisher Game Development Group. Originally published in December of 2007, it allows for Dungeon Masters to bring the world of Barsoom to life for a Dungeons and Dragons 3.0 or 3.5 edition game.
Player Section[]
A brief bit on how to adapt for a world where armor is not the norm.
Monster Manual
The bulk of the book is dedicated to 13 Barsoomian monsters, and variants thereof.