Wallwichen: Three Clusters World Book 01 (2019)

From publisher blurb:

Once, the Orion Arm was humanity's plaything, the Earth Alliance expanding by leaps across interstellar space. But as happens with all our species creates, it was destroyed through greed and lust for power and spite.

A thousand years on, space is still dark, but light sometimes flickers for a while in a little corner here or there. The dream of the Alliance dies hard, and over and over one world or another has tried to recreate a fraction of its glory, only to fail.

Enter the Three Clusters, where it’s happening again. Whether or not they succeed this time depends on you.

The Three Clusters Campaign is a "classic-style" Hard Space Opera game setting, using the PWYW Cepheus Engine rules. for which Wallwichen is the first world book. Players take on the character of merchants, mercenaries, explorers, or many others in a universe where every world is hand-crafted by a veteran game setting designer.