For those aiming for the Hard badge in 2019: Aim for the Cut out study/mastery, Mana pool, and meteor study/mastery. If you know a Ninja champion is coming, stock up your mana you can fire up to 5 meteors in a row.
Easy gold without much trouble: 1) go to Krin and buy max diamonds, 2) go to Pia and sell Diamonds, 3) return to Krin. Also, to make enough gold to begin selling diamons you can go between Pia and Yovella trading Iron and Silver.
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