Master Cyphona:
You're determined. I'll explain the mission then.
Hunt monsters at the Enchanted Valley, Garden of Spirits, Atelia Fortress and Shadow of the Mother Tree and bring Proof of Strength. Hmm... Let's see... Ferin said you need to bring about 10.000
You'll need to go talk to Ferin once the mission is complete so I can't lower the quantity, sorry.
Good luck.