by Teowulff
Ok another try.AQ (original): comes with 9 tiles and 12 heroes and a full campaign.
Beyond the Grave (BtG): comes with 3 new tiles, 2 new heroes and a full set of new monsters, some new weapons and a new campaign. You need the original to play it (for the tiles). It added gravestone cards.
Inferno: stand-alone edition with different theme. Adds damnation and uses brinstone cards (a version of graveyard cards that BtG used).
Pets: adds a new mechanic (pets), some extra heroes and monsters, a few tiles and a mini-campaign. You need either AQ (original) or Inferno to play it.
Dragons: you can add a dragon as 7th scenario (normal campaigns only have 6 scenarios).
The Fall of Arcardia: a campaign book that uses Inferno and AQ (Original). If you also own Pets and/or BtG it opens up more possible scenarios. It adds no new heroes, monsters or tiles.
Masmorra: totally different game but same theme. AND you can use the heroes in AQ (crossover). There's 5 in the base game, 5 more in the Adventurer's Set and 15 Kickstarter Exclusives (of which one was an add-on)
Super Dungeon Explore: different game, no crossover stuff.