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MC's Walrien got turned into a dark prana (think rift mons) and fucking died. Also, from what I've gathered you use heart scales to learn moves and evolve your Pokémon, which you collect from multiple dungeon runs. Another thing is you get access to more EV's by completing achievements.
Held items are different in this game also, where you don't equip them directly, they just have a perma effect from within the bag and also you can have up to 25 (so far) so I've been using held items that help with healing and hyper offense for my dragon Pokémon. I've just been grinding dungeons for a while.
