From publisher blurb:
GWAETH AT A GLANCE
Gwaeth is a world very different from a lot of our other settings in that within this world, science IS magic, and magic IS science. One event changed the face of Gwaeth forever: the discovery of magnesium. An explosive and flammable metal, magnesium soon became a hot commodity in Gwaeth. A few small trade wars sparked as time went on, but today, magnesium is the new adamantine. Used to craft now-refined explosives and experimental engines and firearms, only certain companies are allowed to ship and offer magnesium to buyers. With this in mind, there are three key features to keep in mind when playing in Gwaeth.
1. Colonization occurred and fell, but its wounds and effects still run deep. Gwaeth is an incredibly old world, and much like our own, the lasting effects of the colonization of old empires still remain. Ruins, old family names, coins still circulating. Rather than engaging in colonizing, take this opportunity to reflect and analyze what it does and how much it truly affects.
2. Magnesium is king. Having magnesium is more than just holding a valuable resource: you hold the lifeblood of the primarchs themselves. Magnesium is used for technology and magic simultaneously, leading to it having a worth far far higher than coin can
manage.
3. The Devourers are still out there. The memory of the Drowning Era and the Devourers is still very much alive, even having happened millennia ago. With the landscape so thoroughly changed by it, it is hard to forget. Use this to help really define and shape the landscape as a character in your Gwaeth games. In some places, dead Devourers BECAME the landscape.