My card game is unique in the fact that everyone uses the same deck. I have one deck that splits off into five smaller decks (level 1, 2, 3, 4, and traps). At the beginning of the first turn, everyone starts off with 1,500 food and 5,000 life points. You use food to buy different cards, and the only way to win is to deplete all of your opponents life points. When a monster gets destroyed, or when you use a trap, it simply returns to the bottom of the deck you took it from. Cards get more expensive with level 1 cards costing 500 food, level 2 costing 1,000 food, level 3 costing 1,500 costing food, level 4 costing 2,000 food, and traps costing 1,500 food. Players gain 500 food at the beginning of their turn. Monsters have only one stat, attack, and which ever one has the higher one wins. You have to get rid of a person's monsters and attack them directly to deplete their life points and eventually win. That's a basic overview of the game without going into the more technical details.
I'm a bit pressed for time right now so I can't go into too much detail, but a lot of people refuse to set foot in a church because they feel like they're being judged. If only we could get rid of that, a lot more people might be willing to try it. I have to go now, but that's the overview of what I was going to go into.