I have been playing Lv10 mystery mine for some time with no issues until today. After upgrading bonnie to lv60 & getting her +5% hp bonus to all heroes, the difficulty for mystery mine, with everything unchanged, went up considerably higher. Mobs hit harder & take longer to kill. Bosses dealt an additional 10k damage per hit. Have you guys tested this yourself? Was this done on purpose to hinder players' progress? Honestly, this is a waste of time and I just feel like uninstalling this game.