The Plane Above: Secrets Of The Astral Sea, by Rob Heinsoo
As someone who reads and plays more than my fair share of role-playing games , I often find books that offer unintentional insights, far beyond their ostensible purpose. Such it is here. This particular book is designed for those who are playing or planning high level heroic campaigns for heroes that have seen and done everything and are bored with normal challenges, forcing even more extreme dangers and risks, and even more outlandish scenarios. As such, this particular book has a fairly small target audience, namely those who are extremely serious about table top role playing and who have committed a fair amount of time to study a given imaginary world. Even so, this book offers particular and striking insight for those who take this book as a reminder of territorial and internally divided nature of the fallen world, with a strong degree of knowledge in heathen religious worldviews, as this particular book offers a campaign that bears a striking resemblance to our own planet if viewed from a point of view that emphasizes the spiritual reality rather than a geographical accuracy.
The contents of this book are fairly short, at about 160 pages of material, and divided into four chapters. The first chapter examines some of the issues of in-game astral adventuring, exploring some of the themes likely to bring adventurers into this dangerous place. The second chapter looks at the so-called divine dominions that can be found here, including some details about their history and denizens and geography. The third chapter looks at the deep astral sea, including a look at the races of the area (couatls, githyanki, maruts, and quom) and the shattered dominions that are missing their rulers and are existing in a state of considerable ruin. The fourth and final chapter gives a detailed look at various residents of the region, in alphabetical order according to their general “class” from abomination to quom, with notes on their tactics and special abilities. This sort of information would be useful to those who are planning campaigns in the area, but is likely to be of little interest to anyone else unless they happen to be a student of demonology.
For those who are not adepts at Dungeons & Dragons, there are few reasons why one would want to read this book. Among them is the curious reason of seeing what it is that demons think of themselves. This game has an insanely complicated demonology, to the level that basically all of its gods are demonic in nature, all of them deeply divided among themselves, of limited capacity, and with a certain tendency to deify brave and noble adventuring heroes, serving to blur the line between human and demigod. Great levels of hierarchies and intense competition over honors and offices and favor mark the benighted beings of all alignments here, and they can basically said to be all bad, regardless of whether they claim to be good or neutral or evil. Few people will likely be interested in pondering the various schemes of demons to increase the span of their domains, to fight off the rightful ruler of their domain, or to reverse the isolation brought upon by their rebellion, but for those who have such an interest, this book offers surprising insight.
 See, for example: