With the recent adaptation of Altered Carbon on Netflix, I thought it was time to take a look back at one of the most well-established transhuman-cyberpunk roleplaying games, Eclipse Phase. Sunward is a supplement that focuses on what I would consider the most common settings for Eclipse Phase: the Solar System from Mars (terraformed and under the control of a shady consortium) in to the surface of the Sun itself (colonized by people who have put their minds into highly alien and well protected bodies capable of withstanding the environment there).
Most of the book is taken up by a systemless description of this setting, though the organization of the book is top tier, and inclines it back towards the core action of the game. The typical Eclipse Phase game is based around a secretive troubleshooting/human defense organization called the Firewall, about midway between a secret vigilante group and a hacktivist syndicate. In Sunward, each chapter head acts as a mini-table of contents for that chapter and is pitched as "things a Firewall agent might want to consider when operating in this environment". Sometimes it's about typical threats or environmental dangers, sometimes it's about "unofficial" rumors, sometimes it's about the "secret history" of the world which Firewall navigates and discovers.
The remainder of the book includes new bodies for characters to use in different environments, some new threats and equipment stats, and, as is usual for Eclipse Phase, several sample characters who operate in the setting being described.
The typical criticism of Eclipse Phase was "wow, but the system doesn't do much, and what am I supposed to do with this?!" It's clear the creators of the game took this criticism to heart when working on supplements, because Sunward is very carefully aimed directly at the bullseye of what Firewall and the actions of the PCs are expected to be. They're expected to be scientific and espionage operatives infiltrating or exploring hositile environments to puzzle out the truthg of the chaos that a ultra-high-tech war left on humanity, and interacting with the human and near-human entities that form the blurred line of the transhuman sf experience. (The system is still kind of a wet noodle, so if I said we should improve this supplement it would be in that area. Also, I think for the bodies which the PCs might inhabit when (say) travelling to the Sun or Mercury, it would make more sense to have them on single-page pullouts, or cards, so as to easily distribute and keep them separate from the "minds" of the player characters on the core character sheet.)
Sunward is a great example of what a supplement should be. It enhances the understanding of the corebook, is easy to tell how it should be used, and has form factors and is structured in a way as to make it easily accessible. It gets my highest marks because of these traits.