My current team is:
Lucina (+spd/-def)
Nino (+def/-res)
Ninian (+res/-spd)
Eirika (+hp/-res)
I recently pulled an Ephraim (+def/-hp)
Should I swap out Eirika for Ephraim (given that I'll get Hone Speed on Ephraim if I do decide to switch)? Will Ephraim be able to handle any key characters Lucina/Nino can't handle, or will he be doing the same thing Eirika is doing right now (which is being a buffbot)? I feel that a blue would be much better for my core (Lucina/Nino), but I also feel that Lucina/Nino can handle most if not all of the meta after 1 Eirika buff.
Lucina has fury, desperation, and reposition inherited, and Nino has desperation and moonbow inherited, if that affects anything.
You already have a sword user which is Lucina, since Ninian isn't meant for direct combat unless when brute force is necessary, I'd say swap Eirika out for Ephraim just so that you have another blue unit who's actually capable of combat. Plus your team is pretty squishy.
I agree to many sword users out right now. I only roll with 1 red at a time. My mind set is everyone is thinking the same thing so they are packing more blues and you don't want the disadvantage. If you like Eirika for her atk buff just throw on hone atk on Ephraim. I use Linde so Eirika is the red I use with Ninian as dancer
Let me play devil´s advocate here, and say that i personally would rather play eirika than ephraim.
Blue units that eirika would be soft agaisnt can be hanlded by nino+ninian quite handily.
On the other hand, hector, an enemy nino, or a julia could be a problem if lucina cant catch them in time, not to mention if, by some chance, she gets a hit in before actually dueling them.
I think eirika can use a swordbreaker if it comes to it, so she can team up with ninian to get rid of any sword lord giving you problems too.
But if its a green unit giving you a hard time instead, there is nothing ephraim can do, and i find its a lot easier to deal with blues using nino than with greens using lucina.
I wish I had seen this earlier since I run a pretty similar team and actually was in a similar spot. My team consists of:
Ninian (Neutral)
Eirika (Neutral)
Nino (+Spd/-HP)
4th slot is usually a bonus hero, or is swapped between Michalis/Sanaki.
Now, I never had to choose between Eirika or Ephraim but I did pull a 5 Star Effie and had to make the choice of running her or not and my experience showed me a couple of things. Running two Blue units (one being a dragon) and Nino left me VERY vulnerable to G Tomebreaker 3 Julia. She can be played around but it usually means killing off Eirika by putting her in a bad spot which unfortunately ends my deathless run right then. It also taught me that I really don't need a Red "counter" per se, but instead just need 2 Red "checks".
I ended up taking Effie off the team and instead gave Eirika Fury 3+Swordbreaker 3 and gave Ninian Triangle Adept 3. Those two units now check every Red unit I've come across so far rather nicely and I can devote the rest of my team to getting rid of Blue and Green units that are gaining popularity.
To be honest, you could run either and get virtually the same results because you have a unit that already beats 29 of 39 Red units in the game. Nino with +3 to Atk (Sieg weapon), +4 to Spd (Hone Spd), and +4 to Def/Res (Rally Def/Res) while in Desperation range (give Nino Ardent Sacrifice if you haven't yet) while using Life and Death 2/3 beats 29 of the 39 Red units in the game. If you can't get a hold of Life and Death 2 (which isn't actually that bad to get) then Fury 3 is a suitable substitute since you only miss out on 3 ORKO's (Caeda, Eliwood, and Fir). Honestly, the only commonly used units you don't ORKO with this setup are Zephiel and Sanaki of which Sanaki just counters Ninio and Zephiel just dies if you dance Nino and re-attack. Nino is such a beast that either one will work.
If I were in your shoes, I would make my assault team run Nino, Eirika, Ninian, and (insert bonus hero here) with those sets. On my defense team, however, I wouldn't run Nino since the AI doesn't know how to pilot her. I'd probably just run units that are hard to deal with like Ninian (dancing unit), Lucina (Lucina), either Ephraim or Eirika (Ephraim better limits how they can position their Red units but is prone to getting Doubled really badly. Eirika is less prone to being doubled but doesn't handle Reds quite as well), and a hard-to-deal with Green unit. That Green unit can be anything that just gives people trouble or makes them have to think twice about their action, people like Minerva, Michalis, Julia, Hector (if you're lucky enough to have one), even a unit like Raven. Just something that's threatening enough that the opponent CAN'T just position haphazardly to succeed.
Those are my thoughts, beating the AI is usually easy enough to the point where Nino+buffer+dancer is enough to just wipe the floor with it and I think a lot less about my Offense team than I do my Defense team. Beating the AI is easy, giving your team to the AI to beat the player is much harder.
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