I buyed the "duel"-expansion.
As I know, the beginners-game, "First Catanians" is free, but the expansions of the card game need the CU-expansion, called "duel" or "rivals".
There are 3 expansions of the card game, which you can play seperate, or "duel of firsts" with all 3 expansions. Like I done here.
It´s more to learn as in board game "First Island", but my opinion is, it´s more funny.
But for a good player are the AIs to bad. It would be better with a human "enemy".

How do you play this?