Janus

Janus is a card game with an interesting twist: cards have symbols on both sides! And while you see one side of the cards you're holding, your opponents can see the other side of your cards...
Another interesting twist is the possibility to take the card from the draw/discard pile, or from other player's hands. But in both cases you always cannot flip the cards, so you can't know what is the symbol depicted on the "hidden" side of your card (until you discard one of them and someone else pick up it)...

There are 66 cards with 10 different symbols. Goal of the game is collect as many sets of 3 as possible.