Heck, I beat one game of Mazes and Mahars after discovering it ... 2 days ago and playing about 3 games. No wonder that book is so rare :'D But I had fun. Do the cards change the more you play?

The cards don't change much. After a couple of games you should see most of the cards, if not all the cards.

I love playing it, but rarely have time because the game can take a while to play and the reward is pretty insignificant - at least once you have all the achievements.

Eh, what's there is pretty cool too. A nice way to get into tabletop games!