one more piece of advice, the way i beat hard campaign is to use either a deck dedicated to building or attacking. building worked better in most parts, but if computer castle starts low, go attacking to try to finish him quick. and just keep trying
and for all those complaints about quitting counting as nothing, they dont count towards game stats but i think they count towards the badge cuz i was credited with 4 wins, one person quit and i still got the badge.