How to fight ??? in Korone Box

wowowow-korone-box

One of the achievements for WOWOWOW KORONE BOX says to "Defeat ??? on Hard Mode". Who is ??? and how do I fight them?

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Best Answer

??? is Dark Korone. She will appear when you open your 48th box in Normal Mode and 36th one in Hard Mode. She is your doppelganger.

You can see the fight in question in this video.