Try to use the pergamin (You can bought it in the Tsubaki's House); it had Health Body (No altereted states) and Overpower (Magic and Hits increase a lot). If they don't appear just restart the day with a load state before (call it a day)
Explore all the maps to hidden chest (the red ones only with the blonde girl) and finally craft your build with a good level
My Build it's
Demon Sword
Warrior Helmet
Demon King's Armor
Blink Shoes or Eart Shoes
And Power Gauntlet