I got one in cyl and it is +spd -res I already have a level 40 +spd -def do I merge if so which one or fodder if so for what and on who.
The recommendation is usually to fodder odd atk wave if you're going to fodder her. There are different schools of using odd atk wave; I'm in the camp that likes it on units that function without it but enjoy having extra firepower some of the time, which means not on blade mages because atk buffs count double for them so they want them on all the time.
Well, that depends on what would you like to do with Ishtar. Are you gonna +10 her? if not it's better fodder her since you already have one.
My recommendations are units with Bladetome, strong units that usually like to attack on player phase and on units that don't blend well with your team to be able to use Tactics or Movement Buffs.
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