when you compare adventure packs (or the core set senarios) from DL = 4 to DL=7, Exactly what it is about it that makes them so damn hard according to the DL rating?
This depends on the scenario itself, usually one of the following:
- unique scenario limits on what you can do
- ration of locations to monsters in the deck
- average threat strength of locations and monsters
- average engagement cost of monsters
- location and monsters special abilities
- encounter card synergies
you get the gist. The best way to gauge difficulty is through repeated trials win-lose ratio.
Yes, buy the expansions if you like the game and can afford it. Not only the overall game will get better because of new cards, but they are usually, imo, low cost per hour of enjoyment.