So, I managed to complete all three difficulties for Linus, so I have three versions of him. Since I don't want his A skill going to waste by merging, I'll use two copies to give some units Brazen Atk Spd while I keep the 3* to train. Meanwhile, my eyes are on those with Desperation, which syncs pretty well if you don't mind the 5% gap between the thresholds... There are other contenders, too.
I decided that one of them will go to my Ayra (+spd -res), as the bonus speed will go a long way with her signature weapon and combat skill as well. As for the other one, this is where I'm stuck.
With Desp:
* Lyn (+res -spd): While this can replace her default Defiant Atk, it can also remedy her speed bane. She is keeping Sol Katti, which has built in Desp, so that explains why she's here and not the other list.
* Caeda (+atk -HP): Once she gets her Wing Sword and it gets an effect refine... Currently has Darting Blow.
* WoF Hinoka (+res -HP): Her Atk Spd bond is good and all and melds well with my strat of grouping my units together, but there might be a chance she'll drift away from her teammates.
* Soren (+spd -atk): Would help patch his bane, though as a supermerge he would have beastly speed; moreso if he's got allies surrounding him due to the eff refine. Currently has Death Blow.
* Felicia (+spd -hp): Kinda so-so about it, but decided to put her into consideration. But hey, that could mean more devastation with her plates once she reaches that point. Currently has Mirror Strike.
* Tailtiu (+spd -res): She may be a 4* merge project, though I can see potential. Currently has her native standard atk res buff.
* Siegbert (+HP -res): He can tough it more easily, and he could be fearsome after hitting the threshold. Currently has his native Death Blow.
Non-Desp:
* Minerva (+HP -def): If only because her native L&D doesn't mesh well with my playstyle. Alternatively, I can hunt for Fury.
* Sharena: That standard spd skill she has can only go so far. Plus, mine's got Vantage, so that Fensalir's gonna hurt.
* Elincia (+hp -atk): Can help with her bane. Plus, she's kept Ardent Sacrifice, so one use of that support skill, and watch out! Currently has Swift Sparrow. Could give her Desp if I'm fiendish enough...
Since you give one to Ayra, I'd give the second one to a non-sword unit.
Personally I think Soren is a neat idea, though I really think you should promote a 4* with better IV's and merge him.
If you use Soren, you can let him tank a hit first with the owltome effect and then fly out when he's in desperation range.
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