Any game that could be played with other PCs is cool. And if its a card game, would be awesome if they force us to collect all of them all arround the world - another reason to explore and have fun, maybe even force players to party up and kill some higher lvl mobs lvl60+ or so for the better cards etc. IMHO its very importaint to add something of the sort to keep us busy while waiting for those 15minute cooldowns of the instance re-entry... Dont let your customer get bored!~
