Looking for a merge project. I'd like it to get me higher arena scores, but absolute top tier is not a priority. I'm floating between 18-19 right now.
Long term the objective is to have at least one 40+10 green, red, blue, and colorless. I have a green unit almost done. My red unit with the most merges is growth-limited (Masked Marth, at 40+5), so she will need to be replaced eventually but I don't want to work on a red merge yet.
Giving passive thought to Clair, Florina (yes really), Jagen (yes really), Reinhardt, Lukas, Robin, Tailtiu, F!Corrin (standard), Mae. Others don't jump out, but I could be talked into most of them. I have lots of 4* Effies but I don't have much of an opinion on her. Definite no-s are (1) Cordelia because galeforce fodder, (2) Odin because he's good skill food generally and his stat spread is disappointing, and (3) Nowi because everyone and their dog is using Steady Breath Nowi, omg please stop, and her personality is great for the narrative but hearing her shout "Let's play!" or "Rawr!" for the thousandth time makes me feel like I'm babysitting in purgatory.
Pity so many of my favorite blues are limited availability.
Armoured units like Effie or Gwendolyn score really high in arena. The usual DC+VF build is recommended for both of these units, but its rather expensive to have. I have to wait next month In the LB just to get M!Grima as fodder. There's also a banner with Hector on now. With the correct Ivs they should preform well.
Shigure gives a good combination of scoring potential and overall strength. Also having a flying unit in your team always helps with enabling a more unique playstyle (for example tactic skills, guidance).
Donnel is also great if you don't want a flying merge project. He has excellent stats overall and you can build him in a variety of ways and would be my personal choice when going for an arena merge.
Honorable mention goes to Lukas, who can easily become unkillable when it comes to physical dmg duels.
I would definitely go for Lukas or M!Robin honestly. Both are pretty sound units. Lukas is a lot more fun imo, but M!Robin was in my first arena team, so I have a fond attachment to him. :)
Florina sounds like she'd be fun though, and I'd love to see you build one up. ;)
I recommend against Tailtiu unless you're getting rid of her native weapon. This unit operates more off buffs than raw stats. I would say similarly for Reinhardt; his attack is about all he needs unless you're doing an owl tome build (which does get very potent with emblem buffs and his naturally high defenses). Clair is very meta-relevant; Lukas is quite narrow to me. Mae I think is worse as an offensive mage than Tailtiu and the 5* exclusives.
One very solid option not on your list is Donnel. He can build many different ways depending on your play style. The only thing I don't recommend is a spd-oriented DC Berkut's lance build, which I would say is simply a worse Nowi.
I'm working on Shigure personally and hes an absolute blast to use. He's very flexible in his builds. Harmonic, Firesweep, Slaying, Berkuts, you name it. And he has the highest BST out of all the lance fliers.
Before Shigure I was working on Oscar but with cavaliers not being that great and Shigure being pretty much a better version of Oscar I'm holding off on him.
Some people are speculating the whitewing sisters might get a weapon update so maybe Est and Catria whenever that happens.
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