This is a bit of a rabbit hole but I'll try to explain it.

Core box 1 is the main game that includes a few 'expansion' modules. Up until recently that box plus the Exosuit Commander pack for minis is what got us up and running. There are/were a few promos to be had as well.

With the recent Kickstarter a set of newer expansions are being created. Again these expansions are sets of modules and variants that you can pick and choose from. As a personal aside these are great once you've played Anachrony a million times but I'm not certain they're a day 1 must buy for a new player. These are Fractures of Time and Future Imperfect.

Coming next year there will be an Essential Version released, which will contain just the core game at a lower MSRP. That original core experience will then be available in 3 boxes... core, exosuit, and first round of modules.

Add to that the two new module sets and you have a total of core, minis, and 3 expansion sets of modules for the whole line.

Hope this helps.