GamePress
ⓐⓚⓘⓡⓐ
Boon+ Def Bane - HP

Skill Set

Hero Build Overview/Explanation

Duo Idunn is an armor monstrocity on a whole new level. Just by having an ally within 2 spaces or active buff up she gets the standard Idunn effects and more. 6 attack penalty on the enemy during combat and follow-up negation are just making her harder to be obliterated.
Having her Duo Active skill also makes things easier for her since it provides +6 Def/Res and Armor and Dragon Effectiveness immunity for 1 turn to units on a 5x5 grid where she is in the middle. Its quite possible that she would be the reason why people will start using Duo buildings (Duo's Indulgence for Offense and Duo's Hindrance for Defense) on Aether Raids.

Reasons for the build I recommend.
Defense Asset: Having defense for an Asset is the best choice because she gets 4 more defense making her be at 41 defense on 0 merges which is the same amount of resistance she has on neutral.
Aether: Boosts the damage output Idunn can deal and provides her sustainability within the match. Compliments very well with her Special Fighter.
Distant Counter: General usage to cover ranged attackers. You really want to maximize the adaptive damage effects that dragon units have.
Special Fighter 3: Its a great skill to use on armor units that are general fast or have ways to double on an enemy.
Threathen Attack/Res 3: A skill that lets you get buffed and actively debuff enemies nearby. Goes very well with her weapon especially when she is not within 2 spaces of an ally. Alternatively Threathen Attack/Def 3 is fine also.
Quick Reposte 3 Seal: Her only way to double during enemy phase. Goes very well with her Special Fighter since it does not provide and follow-up guarantees.
Assist skill: Swap is generally the assist to go for armors. Resposition is fine and Pivot is decent when using armor units on autobattles.