Diamonds (2nd Edition)

This is a must have if you like trick taking card games. Instead of having a trump suit, every suit has a unique action that happens when you play a card. You still want to win tricks though, because you gain the lead suit's action again. Also if you have majority in a suit at the end of a round, you gain those suits' actions again. Most points from collected gems wins. The addition of the thief variant for the Clubs action in this edition is a huge improvement.

I have played this with gamers as well as with my in-laws, and it's gone over well in both contexts.