I don't recall that area to tell you the truth, the last area I have gotten is Graveyard (after I beat game), let me get the charger, my battery died 5mins after I beat the game was so lucky to win. Thing for me, is I haven't had a different altois prairie level since I had 3 level 50 dragons... so I don't know when it gets harder. But I found it easy once I had the skill Dragon Slayer.
