Hey, I set myself a goal to make a +10 three-hero core, which would cover the color spectrum. I finished blue recently, which was Nowi. Her main role is enemy phase tanking. Soren is eventually going to be the green choice, but I will keep him as the last step.
Now comes the more difficult part tho, because I'm going red next and I'm kind of unsure which direction to take, so any opinion will definitely be appreciated (btw Tiki is out of the question, because I don't want to focus my team purely on enemy phase).
Eirika: would be a solid choice, which would be universally useful thanks to her sword buff and would be mostly a support.
Marth: most likely better than Eirika, because his drive buffs are more reliable. Also could be a great ally for Soren.
Soleil: high bst, would probably either take a firesweep route or would become a duelist with slaying edge.
Athena/Fir/Lon'qu: these are all high speed, desperation sword users and would be pretty much only useful during player phase. Fir seems like the best out of these, because she has a prf weapon and she wouldn't mind getting stuck next to a mage, because she can take the damage.
Caeda: really useful thanks to her effective dmg and flying movement, but might struggle without flier buffs when in a mixed team.
Lilina: pretty much a yolo option and most likely not a good idea next to soren and nowi.
Maybe +10 Olivia? Dancer is always good.
Or Corrin (M), and pair him with Nowi for ultimate support.
From heros that you pick Solei is strong choice, but she will be harder to merge because she is 4-5 star.
Eirika is in my opinion best buffer in the game, but her real strenght is in mixed teams where you get +6 buffs.
Liliana is realy fun to use, but in hight arena tiers even her 73 raw damage can be not enough.
I completely forgot about Olivia. That's a good idea actually! She wouldn't be too much of an offensive force, but she would definitely be useful.
Corrin also came to my mind, but I'm not too convinced about his effect, because it gives the buff to only one hero on the team, which seems to me like a waste when there are two other heroes on the team, that could use the buff just as well.
I would advice Hana, she's one of the strongest player phase reds (for ftp at least), and if youre in the high leagues, youll be able to profit from her natural armorslayer to get rid of pretty much anything. Otherwise you can always go with a slaying edge, wo dao or brave sword. Shell pretty much do anything player phase for you.
Nowi performs very well in taking damages and fighting back but not a strong character that initiates the fight. I think Lilina can help to clean most of the green units from range attack so that gives Nowi a better environment to tank damages. If you are also building towards a infantry pulse team, Lilina is also a choice for your core.
Marth is your onnly choice, looking at your team. You need a dedicated check for dragons and greens, Marth can do that. And while he isn't, he can provide +5 to two stats and +2 to the other two. Both very useful for Soren and Nowi.
Do realize that longterm, investing in a mage and a low BST swordsman is not very efficient for Arena.
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