Instead of Swift Sparrow, I've thought on run Fury on Eir, she'll only lose 1 HP in each attack, and reaching 49 atk 40 spd 17 def and 37 res if she's neutral. What do you think?
FINALLY, SOMEONE ASKED IT! I think it would be a great idea. she gets the stat increases and she doesn't lose anything. Mystic Boost is great enough already and the healing after combat is a nice plus. Also she doesn't lose any HP outside of the damage she takes in combat, Fury 3 deals 6 damage and Mystic Boost 3 heals 6 damage. I think Fury/Mystic Boost is one of the best synergies out there for a F2P player to build.
She'll be losing 4hp per attack after Mystic if she has any visible buffs. Her hp is kind of low anyways and since you aren't running Desperation, it probably isn't the best idea. I thought about running it myself, but I personally plan to keep her around primarily as a staff killer.
Well you only lose the hp from her weapon when she has hp >= 50%. So once she hits 50%, she'll stop taking damage from fury. Or you could simply use a different weapon on her, like the barb shurikin. Or you could give her reciprocal aid to have her swap hp with an ally, as her C skill will heal them back up anyways. That's what I'm thinking of doing with mine.
every answer I have seen here so far is wrong, even the question is wrong.
When she runs Fury 3, she takes 4 damage after combat. this is because she would take 10 due to her weapon, but Mythic boost 3 reduces it to 4 damage.
That being said, Fury is wonderful on her.
If you worry about her taking the 4 damage until she puts herself to 1 health, don't be. her weapon only damages her when she is above 50% health, so once she crosses that boundary, she stops taking the 4 damage.
Of course in order to make the best use of her, you need to keep her above 50% hp, lucky she has just the skill to do this.
Her C skill, Sparkling Boost, heals 10 damage to whoever has taken the most damage, except for herself. This is easily abused by units such as Micaiah, who can use her personal command --Sacrifice-- to fully heal Eir, than get healed by Eir's c skill. Micaiah also takes care of Eir's counters, armored units.
Just about any unit with ardent sacrifice will work amazingly with Eir.
Fury is also better than swift sparrow considering her base stats. Her high res makes her perfect for mage baiting, however, running Swift Sparrow confines her into a purely offensive role. For the cost of 1 atk and 1 spd, Fury allows Eir to run both phases and increase her bulk.
Her weapons built in swift sparrow effect even works on both phases, so confining her to offense is ignoring half of potential.
TLDR; Fury > Swift sparrow
I have attached my Eir below, the keen eye will find that I have hidden my friend code should you want it.
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