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So in level 6 you run into this Spirit Mirror Pendant, a necklace that makes you earn XP 25% faster.
What did you do with the pendant? Did you give it to one of your characters for the rest of the game, letting that character outlevel the others? Or did you move it around, always handing it to the character that was falling behind in levels so he could catch up with the others? I'm inclined to use it in the latter way.