I see, too bad. W/ the bear I was able to get to 15 in like 3~5 days (Got a good combo of 2 common cards, Attack opp hero = Restore Heroes life plus Healing = + Att for all cards in play)
Anyways, yeah, another change I notice was that most of the legendary and epic cards were already unlocked, unlike MP. Also, some of the cards abilities seem to have been changed, like Leaf Lady. Made it difficult to blast through the maps.