Okay, so this is more in line of what I was expecting from metaplot/plot/campaign books than what Cutting Black was. It seems to be completely disconnected to the 6th edition metaplot and I'm not particularly well versed with Shadowrun MO to know if this is because its essentially standalone book or if stuff in it will be important or come back later. Anyhoo so this is about mysterious piece of code named after a japanese youkai which when activated manipulates markets in semi legal fashion to produce lot of money. There is bit long in universe article about market manipulation and coding which isn't really super interesting to me since not that interested in stocks and economy, but I like how adventure/investigations presented in book demonstrate different way codes can be used and different stories you can tell with it. I didn't read everything in detail because I never read sixth core rules in first place so I have no idea how it works rules wise in practice, but the investigations seemed solid and varied. They seemed like they would be easy to use as is and work as inspirations to build more adventures to do with subject matter. I do think the in universe conspiracy theories about trying to figure the origin and purpose of the code went perhaps bit too long since it started to feel as frustrating as reading real conspiracy theories :D