Then the Twilight Map will help you for everyone. For characters with a Light weapon, the map with Dark Ganondorf will be the best (The description is something like "Stop the enemy's devicive plan!") For characters with Darkness weapons, you'll do the same mission except against Dark Fi. Zelda can do both since she has a light and darkness weapon. I forgot the other ones, but I'll post it here later.
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Found it.
For Fire weapons, the Lv. 12 Rack up your KOs mission.
For Water weapons, the Lv. 11 Rack up your KOs mission.
Sheik can do any of them since she can change her element.
What about electric?