I can see how it might be easy to want to compare Card Dungeon to the ever-popular Card Hunter, but, aside from the aesthetics, the two games are hardly alike. I just wanted to get that bit out of the way early.
Card Dungeon isn't a collect-a-thon with multiple characters on a grand adventure, it's a roguelike. A roguelike with a nifty board game style that uses cards in place of character skills.
Dungeon hold 'em
Much like other permadeath engines, you'll move along one turn at a time, exploring a dungeon and dealing with the unfriendly denizens within. You'll also gather gear and pickup essential skills (skills that are actual cards, of course). Assuming you live that long.
What I both like and dislike about this card-based system is that you can only carry three cards at a time, and they'll wear out the more you use them.
So you either have to ration the skills you really want to hold on to, or get used to constantly swapping out weathered cards for brand new ones.
It's great in that it encourages you to constantly try new abilities, but it can be problematic when you only find skills you don't need - for example, finding a spell that only heals summoned minions when you don't have any summoning skills.
The lack of a map is also a tad irritating. Not that I think one should be provided from the outset, but if I want to explore a dungeon level a bit more after defeating the boss and opening the exit, I'd like to be able to find my way back when I'm done.
Heck, even being able to zoom out a bit more would be fantastic.
Card Dungeon is a bizarre mash-up of genres that works better than I'd expected. It's more about dungeon exploration than card collection, but it manages to make both quite entertaining.
Until you die and have to start over, anyway, but I'm into that sort of thing.