I'm sort of glad that they added a difficulty level of this type, but just before I start wasting stamina on this, I wanted to ask the people who already won the Infernal fight whether it can be done with heroes that are not +10, because the opponents seem to have their stat boosted pretty high.
Wish it was Clarisse instead of Legion though. She seems much cooler.
Its possible, I ran with Xander, Camus, Priscilla(with speed buff for Nino), and Nino. But, sadly I have no idea what I did except the first few turns(which is using Camus to lure Red mage and Archer, and killing blue mage with Nino). Was constantly extremely close from loosing, and at a certain point, I even had to made my units escape across the map. All I can say is, you need to utilize movement ability a lot(Pull back, swap, etc).
Took me 90 stamina, good luck.
It is definitely doable, though you might need to tweak things with skill inheritance quite a bit. I wasted a lot of tries with Nino, Eirika, Olivia and Robin for example, but in the end I got a situation where I wouldn't be able to kill the final unit (due to it having Vantage). Replaced Olivia with Azura, used the same strategy, won this time around. That being said, high-tier units definitely are recommended. A red mage (or Nino) with Axe Breaker as well.
It's possible. I did it with horse emblem, all 5*, no merged units. My team was Reinhardt, Abel, Cecilia, Xander. Attacked the Legion on the left with Rein, and the Legion on the right with Cecilia. Abused the terrain and killed all but the archer on the next turn.
Oddly, there were no enemy reinforcements for me when I invaded the center :/
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