I suppose since team profiles are a thing and I've meant to do this anyway I might as well get around to it.
IVs: +Spd -Res
Catria is the dark horse of the team, rarely discussed in the arena meta and having never been featured as a banner focus hero, which is funny since I have a +4 merge on her.
When talking about blue melee units, they've traditionally been used as baits for killing red melee units. Less popular since arena matchmaking changes and skill inheritance came out, as ranged is just generally safer to use for perfect run streaks and don't come with an MMR penalty. Plus setting up offense is easier on player phase, with stuff like Darting Blow/Death Blow/Swift Sparrow only working on user initiation. So the blue melee units that do still get run are generally sturdy (Ephraim's a good poster child, but even relative unknowns like Lukas and Subaki are best in this role over more offense-oriented lance users, such as Cordelia. Or NEB's pick for severely underrated, Corrin-F.) Usually they pack Quick Riposte to emphasize their approach.
Catria is a more balanced version of Subaki, trading some defense away for an actual attack stat. Typically you don't really want to go for balance in constructing arena teams (win really hard at what you do, avoid matchups that are bad for you) but I feel like I've managed to get away with it. She may not be optimal but due to RNG dumping 5* Catrias onto my lap I've adapted to using her for the sake of ranking, and she was a personal favorite as I was leveling up early on so the preference kind of stuck.
Your A slot selection, on the other hand, gets weird with a unit that's primarily supposed to bait. You can run Triangle Adept (or a jewel weapon) to solidify WTA matchups, and this tends to be the default approach (Subaki comes with a Sapphire Lance, even). You don't really want to run stuff that only powers up on initiate. Speed+3 was my default selection at first but feels underwhelming compared to the competition. Fury is also an option but taking chip damage on every combat session on a unit that's guaranteed to get hit can also be awkward, and can put you out of your QR threshold.
However, running TA feels kind of bad on any unit that has a jewel weapon as an option, on the other hand. It's justifiable on units with unique weapons (Eirika for instance) or with raven tomes (double super WTA!) but outside of those, a jewel weapon trades 4 Mt for TA's effect. This is... probably a winning trade, with the closest comparison being vanilla 15 Mt weapon and Attack+3 in A slot (Attack+3, like Speed+3, just feels underwhelming).
I tried Iote's Shield for a while as well, but was quickly unconvinced; archers became less popular and as a flier you have the ability to pretty much pick where you want to fight, so it's really a non-factor on offense.
So in the end the Hero Fest banner came out and I yanked a Hector to feed Distant Counter, which solved my conundrum (now she can effectively bait and kill red mages, Nino's greatest threat).
The B slot also merits some discussion. Again, with the above supertank builds of Subaki and Lukas, Quick Riposte lends naturally to that sort of setup. But since Catria is more balanced, can get hit below QR's threshold (even at 3 it's only 70%, and exclusive to 5* Subaki) and I'm not actually running a jewel weapon on her, it feels like a more questionable choice. Vantage, on the other hand, is safe and useful across many situations, is relatively easily activated, and even against green units Catria is sturdy enough that she tends not to die in one hit. Comboed with Distant Counter it's even better, of course, since you can bait ranged units into dying without actually taking a hit yourself.
Hone Speed and Rally Attack exist solely to pump up Nino. The reason I picked that over Hone Attack/Rally Speed is prioritizing the flexibility to be out of position and still give Nino her most substantial attack boost over freeing up Catria to be able to attack on the same turn. She's still best at baiting (Vantage) and as a flier, the mobility gives her better rein to be where she needs to be to do that, as well as making it easy to orbit around Nino (and the rest of the team).
Luna is chosen because of the Killer Lance; while Moonbow activating at 1 can be great, it can also lead to annoying situations where you waste your proc. With Luna, bait hit -> counter will charge Luna, and because of Vantage, you can bait again for what will usually be a fatal hit. A single Moonbow counter doesn't tend to OHKO anything.
I do wonder if Killer Lance is her best weapon choice though. I've argued myself out of wanting to put a jewel weapon on her, but there is a serious case to be made that the vanilla 15 Mt Silver Lance could come out on top in some situations. I think the ability to quickly charge Luna for a decisive hit wins out, but it would depend a lot on mathing out kill thresholds for matchups.
IVs: +Spd -Res
Olivia be dance, dancing is great. Especially in arena where you want units to live, the extra insurance with mobility and potential to snowball offense is awesome.
Fury and Ruby Sword make her into a surprisingly fierce attacker, albeit one with a limited number of uses per battle - which is fine, since she should be dancing most of the time. She kills Hector for free (I still don't know why so many people run him, but as long as they do this will remain a decently valuable role), and with Swordbreaker she can tango with red sword lords that would otherwise threaten Nino. At 41 Speed she isn't exactly worried about getting doubled or getting doubles against opposing breakers as well, which is great.
The choice between Fortify Res and Fortify Def is debatable. Def comes up a lot more often overall when you look at the actual head count of units and their weapons. But in arena, I find mages to be the scariest threats, as it's hard to avoid taking hits from them at times. They can probably be interchanged without too much impact as the main goal is to provide another stat buff to feed to Nino.
She gets the Speed+1 seal because it makes more of a difference for her than Catria.
IVs: +Atk -HP
Nino does her best, and I was using her before it was cool. (Which means like a month from the game launch, when green mages were basically non-existent due to everyone running red sword lords and them being the arena bonus heroes.) Even then people were talking about her potential a couple of weeks in, due to Gronnblade's potential for some ridiculous damage figures.
Anyway she is the team assassin, and does by far the most workload. Blues are deleted in one attack, with only a tiny handful needing a buff to ensure the OHKO. With zero buffs/Spurs/whatever Nino does 66 damage in a single hit when initiating against blue, 58 on a counter. Only one particularly Res sturdy blue unit, Ninian, survives at neutral IVs (neutral 42 HP, 27 Res). Blue mages (Robin-M, Olwen, Reinhardt, Bunny Lucina, Linde) all get OHKOed, and a Hone Attack buff ensures that it stays an OHKO even if they have any shenanigans. Melee units have worse Res and usually mediocre or bad Speed (few blue lance speedsters exist compared to red and green) so they're a foregone conclusion as well.
The IV selection is a departure from the standard Nino build, which is actually +Spd/-Def or Res running Fury 3, giving her a comfortable base Spd of 42. Any team running blade tome mages will typically be running Hone Spd as well, so at 46 she doubles <= 41, which is a huge swathe of the meta. Fury also bulks her up to ward off OHKOs, which is pretty important because she sits on some dangerous thresholds (-Def gets her OHKOed by +Atk Takumi, and -Res gets her OHKOed by a Julia with 7 extra Attack, who is extremely resistant to being OHKOed herself.)
However I concluded that the speed advantage is actually better on paper than it is in practice. Let's examine this some:
- Doubling red melee lets her get the kill on a Lucina (although that's not guaranteed: +Spd Fury Lucina is 42 speed and the meta build). Ryoma (and his inferior version Ike) eviscerate her because of Distant Counter. Eldigan's slow. No other red is really relevant right now or plays support roles (Eirika/Olivia), and those often run Triangle Adept or Ruby Sword, letting them survive regardless.
- Red mages counter her, which is bad and usually fatal, so speed doesn't help there.
- Blue units, as discussed above, pretty much get OHKOed so doubling is overkill. At worst a Hone Attack buff erases any doubts.
- Green melee units are a rarity, but the ones that currently see play are Minerva, Cherche, and Hector. Life and Death 3 +Spd Minerva does clock in at 41 Spd, but she also gets OHKOed with any hone buff with my +Atk DB3 Nino. Cherche and Hector always get doubled; with Hector he counters, even, so you want to ideally kill him in one hit since he can OHKO Nino.
- Green mages are slow (Julia, Bunny Camilla, Cecilia). The exception is Nino herself (or her inferior version Soren). So your speed matters for the mirror matchup but not elsewhere.
So doubling really only comes into play against red units that don't counter/don't shrug it off from super-WTA, and the mirror. The former feels like trying to fit a square peg in a round hole; why force trying to make the disadvantageous matchup work? (The same logic applies for TA, of course; on offense better to emphasize your strengths when you can usually dictate the terms of the fight.) The latter, on the other hand, is extremely relevant: since I don't run a red mage I don't have an obvious answer to green mages, so Nino will need to be on point for them.
For the mirror, +Atk Nino starts at 49 Attack, and since the point is to OHKO, we add Death Blow (+6), Hone Attack (+8), Hone Speed (+4), Fortify Res (+4) and arrive at 71. Neutral Nino is 59 HP+Res; add a +Res nature, Fury, Fortify Res and she gets to 70, where she is still OHKOed.
In all other situations (where doubling doesn't matter) having the additional 6 Attack is helpful in a plethora of scenarios (+Res/HP natures exist, buffs exist, it can be the margin of difference for OHKOs against injured opponents, etc.)
HP+3 Sacred Seal covers all of those bad OHKO situations talked about earlier that come up from not running Fury. On the flipside the one advantage of being -HP instead of -Res is that Nino weathers the assault from Horse Emblem better, which is important because she's the only person on the team who can do anything to them.
The rest of her skillset is mostly self-explanatory:
- Moonbow remains the lowest charge special and thus the most likely to actually activate in a fight.
- Reposition is the best mobility assist. NEB has largely covered why.
- G Tomebreaker (and breaker skills in general) are like rock paper scissors with similar skills (Quick Riposte, Brash Assault, Desperation), except breaker skills win every time. You should probably run them just because you lose against someone who does otherwise for the mirror matchup. (You can't run into opposing breaker skills in WTA and you're already losing the WTD, so those don't matter.)
- Hone Attack is the best generic hone, IMO (Attack being overall the most relevant stat in a majority of situations). Plus her default, so that's nice.
Incidentally blade tomes are a little ridiculous. 13 base Mt with unique tomes at 14 with a gimmick that is far better than any of them (get 8 more Atk with minimal effort, 12-20 more depending on how crazy you want to get).
