For the most part the universe of Ceteri is TL8 (or less in some areas). It’s a contemporary campaign set in the modern world – but that doesn’t mean weird technology doesn’t exist. Schwarzgerät is a word that means “black device” and has come to mean any sort of science or technology that uses variant, unknown, or weird natural laws. Schwarzgerät are not necessarily reliant on magic, psi, etc., but may be just be devices or science that simply works. (Of note are the Nazis who in Ceteri were modern masters of black technology blending a combination of science, alchemy, and magic together into a cohesive whole.)
Alchemy tends to err on the side of black tech as it relies on principles that are like magic, but not magic. “Regular” alchemy is simply magic in a bottle and uses the rules for spells like any other form of extrinsic magic. High Alchemy is both magical and mundane at the same time. It relies on the echoes of God’s creation to create reproducible effects.
Other black technologies exist, usually the brainchild of a mad genius and one-offs. Such inventions look an awful lot like fringe science to the naked eye and rarely look like they should work even though they do. In GURPS terms, such black tech is created using the rules from “Metatronic Generators” found in Pyramid #3/46: Weird Science.
Picking Over the Bones
This one was one of the more light entries in my setting bible. I’m sure it’ll get use at some point, but I’m not holding my breath. I originally considered making High Alchemy its own thing, but the idea that it was just medieval black tech was too appealing. I’ll note that I intentionally didn’t want the mixture of magic and technology to be a commonplace thing. Too me, it has too much of a Harry Potter vibe and that was something I wasn’t really going for for the most part. The wainscot aspect of Ceteri is important and when you start mixing magic and tech things tend to get . . . weird. That said, I do have some instances of it (the House of Cagliostro of the Conclave is the big one), but such things are typically in the hands of NPCs.