I'm honestly slightly surprised reddit didn't talk about the 5-race boss. 4 of them are pretty easy to cover - But adding Fairy/Spirit to the mix will make it quite difficult for many units to go in fully prepared for max damage.
Well, pulling for xon/Fei means you will probably want jecht too, for what that’s worth. Fei is the most critical one to get right now because he’s limited, but if you’re wanting to build a dark team those three units are key.
Not really…racial damage mods are averaged just like element and weapon resist/imperil/amp. It literally just makes gearing and team comp more difficult.