There's also this pretty good game, we could hold a tournament based on it.

Haha))) Like, everything is based on random chance. Good one, bro!)

Added 1 minute later
Considering we're not some hardcore gamers, I don't see anything wrong with the idea of Hearthstone, especially because of the random element – it's just for fun, but I see many other drawbacks – some people have significant experience, while others don't, and, more importantly, the issue with decks. We could, of course, force everyone to play only with basic decks, but that would kill a significant part of the fun.