With 25k feathers I'm a little uncertain what to use them for first.
Upgrading +def/-spd Sophia to 5* who would then inherit CC and Candelabra from W!Tharja and possible Res Ploy from an extra Gunnthra.
Or using them to give Winter Cecilia CC from the free 4* Takumi we got?
Tharja is a much better unit than Sophia, so I wouldn't even consider making her giraffe food.
Cecilia is a much better choice for CC. She already has the ploy she needs and the Res to run it. Vengeful Fighter would be great, but honestly Wary Fighter will do fine. Take a hit, counter attack, then activate the ploy and strike back on player phase. It's like Hrid's omni breaker, it just takes 2 turns to complete.
Sophia's not a bad unit. But an unmerged Sophia is definitely worse than an unmerged W!Tharja. They do the same thing and a gen2 armour has a lot more stats to do it with than a gen1 infantry. +6 def, +7 res, and +1 atk. Also Vengeful Fighter is a lot better than QR.
If you're going to heavily invest in Sophia then it's worth it but the answer to this question is that Celica should go first. If you just promote one Sophia, inherit to her, and then start working on Celica, you've just made a worse unit to use while you wait to get back to merging Sophia.
Mist's not a bad unit she's just a bad 5*. She's similar to Wrys and Sakura. There are definitely worse units than her.
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