On my level 24 rebirth'd eir, I find it very useful, casting it whenever I can. I like it better then the original moon pieces because its horrible for casting against big mobs where it scatters everywhere.
well its really up2u
I left it on one while maxing my old pieces
To me the rb pieces didnt do good damages..but its a VERY good distraction skill though, u can use it while healing your pt member especially at 6-10..
o_o
I'd keep it at one and cast it whenever you can to keep some monsters from cancelling your heals. If you're a stage eir then theres not much point in leveling it since you'll be depending on your party to deal the damage. You could also try maxing another skill such as Tears, but I guess it depends on preference. =3
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♦ black diamond
Auria : Eir Ignorance is your new best friend. ♪
Migrated to EuLuina and is missing everyone very much. ;_;/
I'm not that far into rebirth yet myself but I think level 1 is fine though to keep yourself protected so that you can heal incase and yea the other party members can do the damage. It is an SP eater and etc. but if you rebirth at higher levels + earn SP through quests, it could be maxed.
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IGNs: League of Legends: Allea
~Arigato KratosAurion-san.