Tip: Make a party with two of the required characters + a fast group damage dealer like Faris/Agrias/Squall/etc and you can clear those missions while you are farming the required monsters.
Another Tip: The next Event/Story/Lost Chapter will probably have lots of these monsters too, so if you are not in a hurry you can get a head start by completing it before tackling these missions.
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Specter x30, Red Bat x30 and Scorpion x50
Rosa’s Lost Chapter: A Prayer for One Dear Pt. 5 (Normal difficulty) has all of the required enemies for this chocobo panel.
