User blog comment:VJ3oy/Which Unit do i need to upgrade the BB LVL of :/@comment-24856421-20141116170842

Altri, of course. Status Negation and Status Relief is only provided at once by one healer: Altri.

Elza's got a fantastic 30 hit SBB and up to 70% increase in Spark damage. Just be sure she's 6* before you start leveling it.

I would say to level Kuda's BB, but don't invest Frogs as of yet. Wait for his 6* to come, and then pump that BB level up.

If Narza (Correct Spelling, not Naza) is your only damage mitigator, then use him once his 6* comes. However, Darvanshel and Oulu are much better for the role since you already have Altri. They have Def. Buffs, and Darvanshel also attacks with BB and SBB.