Eldena has a 3-in-5 chance of joining Clan Nutsy after completion of a mission where the Elda's Cup is equipped. One important note on using Elda's Cup is that it is required for the dispatch mission "Caravan Guard" which becomes playable after Mission #07 "Diamond Rain".
However it isn't gained until completing "Hungry Ghost" which becomes playable after Mission #06 "Antilaws". After it's used in "Caravan Guard" it's gone for good, the only way to get another Elda's Cup is to trade with another player. So there is a very short time frame in which to recruit Eldena.
Like all secret characters, Eldena joins four levels above the average of the entire clan. Eldena is recruited as a Red Mage, and as a bonus she has two abilities already mastered: Barrier and Doublecast.
Red Magic Edit
Red mage command. Use offensive magic.
|Barrier||Bestows Shell and Protect.||10|
|Doublecast||Cast two spells during the same turn.||0|