I really love the Core Set of the AH LCG! Now I want to dig deeper without ending up poor. What are my options?

Good thing: I‘m just a casual gamer. I could get it to the table probably once a week max for an hour or two. That‘s why i can squeeze months of fun out of a set.

But how do I proceed in 2023? There are mythos packs, scenarios, campaigns, cycles, deluxe editions, return to editions…?!

It get‘s more complicated: I‘m from Germany and want to play the sets, that are released here in german.

What I already own:

• 1st edition core set <— only box I played yet
• 1st edition Dunwich set
• 1st edition Carcosa set (someone sold these 3 for 25€)

My questions:

• I don‘t own any mythos packs or anything else. So Dunwich and Carcosa are incomplete, right? Should I sell them? Because:
• Tracking down „old“ (German!) mythos packs to complete the sets I own could end up very expensive and difficult, right?
• The return to-editions are cheap here, but it doesn‘t make sense to play them, if I don‘t own the standard cycles, right?
• The „new“ campaign/investigator expansions are probably the easiest way to get another set, but they are kind of expensive (~50€ each). Still cheaper then buying every single mythos pack (15-25€ each), right?