Somehow I never learned of this while it was big. I learned about it a couple of years ago from some guys who played it like mad in college (to be fair, my college games were Settlers of Catan, Lunch Money, and Mayfair's Cosmic Encounter). I enjoyed it, so I bought a copy. It's seen a few plays. That's actually not a bad thing, as I so rarely play board games nowadays (my last Dominion game was shortly after Adventures came out).
I loved the hidden team mechanic. The neutrals pose interesting wildcard ideas. The only major issue I found was that some of those cards can be hard to read. The contrast is downright terrible on some cards.
I also like the variant where everybody plays a green card. The only issue I ran into with that variant is that new players get the feeling that they get to draw a green card every round. I just need to do a better job of explaining it's a pregame freebie. When I first played it, it was without the variant, and I felt lost when rolling the dice.
I think when I play it again, I'll keep that variant, but I'll add another variant where you do not get to use the card that lets you look at another player's faction. That is too much information at the beginning, I feel. I like giving all of the players the same level of uncertainty. If someone else lucks out by rolling on green and then drawing that particular card, then that's fine.
Sadly, this game has player elimination, but usually the game doesn't last too much longer after the first elimination.