The final boss of the game, Dame Demona is pretty hard and even I had trouble beating her. But here are a handful of tips, and these work. In Old Springdale: Fight the Wicked Yo-kai. They give a decent amount of EXP, and you can level up and get money and items from them. You could also fight Yo-Kai you find with your watch. If you find Miradox (he's in a triangular area) and travel back to Springdale in the present, the Memory Store is back and you can buy Exporbs, equipment to raise your stats, and medicine. You can fight the Wicked Yo-kai here too, but you get less EXP than the Inspirited Classic Yo-kai in Old Springdale. In the boss fight: Aim for the two dragons, after they die, use Soultimate or M-Skill on her. Purify, heal, and replenish Soultimate meters when you can because she can disable all of these features. I recommend putting a healer on your team, in the first game I got by without one but in this game you can't. Try to save your Soultimate meters! These tips certainly made the boss fight easier. I actually finished it! (Credit to one guy for finding out that you should kill the dragons.) I hope this helped!