Tech books are cumulative

[ericthered]

In most games, I only NEED one tech book, and in a low-combat game, basic can suffice just fine. One player might go and seek out a custom weapon from a non-core book, but they write down everything on their sheet and then we're done.

The exception is bio-tech, which usually needs ultra-tech to go with it, but that's to be expected.

Some Genre's require more books, but you expect infinite worlds to use more of the tech books than other settings.