@Leo-J
Go to the Gongaga area, in the beaches there you should find an enemy called BeachPlug. Manipulate him, and cast Big Guard on your Enemy Skill user. That's one of the best spell in the entire game, gives you Barrier, MBarrier and Haste to all your characters for just 54 MP. Also try to get White Wind from Zemzoltt, it's the giant owl enemy in the fields near Junon, again manipulate him and cast it on yourself. It cures all your characters for the same amount of HP your Enemy Skill user has at the moment, plus it cures from almost all ailments and it's only 36 MP
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