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Tip: Make a party with two of the required summon/characters + a fast group damage dealer and you can clear the character usage missions while also farming the required monsters.
Glacial Eye types x20
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Machina’s Lost Chapter: Quick Encounter Pt. 3 (Normal difficulty) has 3 Glacial Eyes in 2 waves, completing the mission in 7 fights.
Alternative option:
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Story Act 2 Chapter 9: 9-19 Merciless Annihilation Zone Pt. 1 (Normal difficulty) has 4 Glacial Eyes in 2 waves, completing the mission in 5 fights.
Lamia x15
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Rinoa’s Lost Chapter: Where To Go Pt. 10 (Normal difficulty) has 5 Lamias in 3 waves, completing the mission in 3 fights.
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Thanks
To the DFFOO “Monster Hunter Guide“, an initiative to list all monster locations in the game (maintained by Marvan09).
To @xcaliblur, @mzpro2 and @infinitus who also contributed tips for these stages in our public DFFOO Telegram group, which can be found here: