At what point can I Encase a Eidolon?

At what point can I Encase a Eidolon? - Person Holding Can With Blue and White Knit Sweater

In Final Fantasy Explorers, there's a quest called "Magicite Permit Exam" which is suppose to teach you how to encase Eidolons. (Monsters that are based on the summons from the FF Series) The quest itself only gives you the clue that you need to use your Crystal Surge (CS) ability, (R+L when your resonance is over 100) and that the Eidolon needs to be low on health.

My question is:

At what point is the is the Eidolon considered to be low on health?

and/or:

Is there a way to make sure that Encase comes up as a CS choice, or is there a way to shuffle the abilable CS's to re-roll for Encase to show up?






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Warframe Eidolon Hunting Is A Lot Easier Than I Thought




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