The package included Peril Cards, Exploration Cards (how the campaign gets laid out), Activation Cards (dictates how monsters activate) and track sheet (chances to get upgraded equipment or lose horribly).
The exploration cards contain an onset card ( initial encounter) three main encounters and 8 other encounters. Without failing miserably and being defeated, the game will run from 10-12 encounters depending on how you've dealt the cards.
I played a quick campaign and found it pretty enjoyable. I was a bit distracted though and only managed to make it halfway through. As you can see, with everything laid out, there's not a ton of table space. 
I had to turn the map and extend the table leaf to fit before I finally called it quits. I was distracted and ran out of time...
I also find I get caught up in whatever I'm doing and forget to take photos.
Today, I thought I'd set up the exploration deck and draw the cards and lay out the tiles to show just how big the game can get.
I kid you not, this was a completely random shuffled and drawn layout. Due to a special rule regarding overlapping tiles, last main encounter is separated from the rest of the map. Otherwise it would actually be partially off the table.
Now imagine the table with player boards, act 1 gear decks, etc and this is huge! I suppose you don't need to leave the previous encounters spread out behind but I think it adds to the dungeon crawling theme.
Overall it's a pretty good expansion. It was good enough to get me to purchase the 2nd coop expansion Nature's Ire.
Pros: No Overlord/fully coop. Everyone wins or loses together. Ability for solo play.
Cons: only utilizes 4 monster classes. The activation cards control how the monsters activate and change each encounter but it's still only 4 monsters classes for the entire campaign. Only utilizes specific tiles. The exploration cards dictate the order they are played in but each tile has the same monster classes in it each time you play.
Definitely a good expansion. I'm a bit concerned about the replayability but Nature's Ire (hopefully) should utilize diff tiles monster classes and knowing Fantasy Flight Games' love of expansions, there are probably others in the works as well.
