As a thought experiment (ignoring availability, just about how good the skills are) I was wondering why not use Brazen Atk/Spd, which I feel is simply better than Swift Sparrow & Life & Death. The only requirement it has that the others don't, is to be under 80% HP. The thing is though, most units that use Swift Sparrow & Life & Death are hyper offensive units that use Desperation, and Desperation has a 75% HP requirement, meaning you don't even have to try to activate Brazen Atk/Spd separately. Brazen Atk/Spd works on both phases, and doesn't reduce your defenses. So why don't I see it in many builds (or at least, in any hypothetical builds)
TL;DR: Brazen Atk/Spd is better than the other skills, (in my opinion), why isn't it seen more often in whale builds?
Because Swift Sparrow doesn't have a requirement for it to work, and Life and Death is for hyper-offensive builds. Brazen skills do work, but they require units to rely on enemies to damage them enough to get into Brazen range, but not enough for said unit to have to tip-toe around the battle field.
While I think that Brazen Atk/Spd is generally better than the other two skills, I am still hesitant to automatically use that skill over Swift Sparrow or Life and Death.
As an example, I will be using my super-merged Hana and Nino. Hana is currently the fastest member of my team sitting at 51 Spd with Life and Death (unsupported) while my Nino sits at 46. If I give up LnD for the Brazen, then both have the same Spd. In the event that the enemy has Chill Spd, both Hana and Nino get hit with the debuff, but in the previous case, only Hana gets hit. This is a situation where I would prefer LnD over Brazen.
Another might be if I am at above 80% HP and want to one-round a 46 Spd unit that would otherwise kill a member of my team. (Maybe an Ayra or Mia.) If I had LnD, then this wouldn't be a problem. But Brazen can't do it in this case.
That's the thing: My team can't afford the change. I can't just replace the seal on one of my units for Spd+3 without messing up the roles on my team.
I'm not saying that LnD is better than Brazen. Hell, I'd rather use it over LnD if I could, but it just isn't always the best skill to use.
When it works, it works and you're right, you can go ham. However, it requires that someone entered a round of combat already: either yourself, or someone else (you can use Ardent Sacrifice to go straight into Brazen range). Either way, you have to WAIT 1 turn to get the upper hand.
That 1 turn is extremely important. For ex. if you have a Linde with brazen against a Linde with LnD, your Linde will get doubled and die before you can even start going.
The point is that LnD/Sparrow give you the tools to fight the 1st turn. Desperation is for the cleanup. If you run Brazen+Desp, you are giving yourself an extremely slow start when you might really need the offense (i.e. the Arena). In GC, however, I can see Brazen+Desp being more viable.
Personally I really don't like Brazen skills. My team is kinda balanced, with each core member taking care of their respective advantageous colours. That's why in my case it is so important to have the skill A slot effect kicking in from the very beginning, so that they can secure the kills immediately and prevent the enemies from going after the other teammates. In my opinion the meta right now is focus on killing the enemy in one round, and brazen skills does not really fit into this. Not to mention you will have to look out for enemy units vantage/desperation or even brazen skills. Overall, I think it is powerful but unreliable skills unless you can kill your enemies without A Slot, which makes it useful to fight against more than 1 unit in the map.
Brazen Atk/Spd is best used on healers, since they can't run swift sparrow and life and death. Best healers that can run are healers that have no defensive stats, such as Elise. If i get a bad Iv robin, that is where he is probably getting foddered to because I really am not a huge fan of armor units.
in most cases, brazen atk/spd is superior because it works on both enemy and player phase but life and death doesn't have a health requirement. Life and Death also has a defensive drawback
swift sparrow is a weird one tho that fits on only a few units that need to keep their bulk intact and can't afford the recoil from fury but any unit using swift sparrow will definitely be using desperation so brazen akt/spd definitely comes out on top
so based on availability and usability, i'd rank it
1. LnD
2. Brazen Atk/Spd
3. Swift Sparrow
Simple really. Brazen Atk/Spd for bulky and fast duelists, bonus points if they have skills like Wrath, Vantage, or Desperation. They can definitely afford to take a hit and destroy units on counterattack. LnD for glass cannons with low HP who cannot afford to take a hit or debuffing units. Bonus points for units whose targets cannot counter-attack. Swift Sparrow for middling defensive stats who want to preserve their defenses but still capitalize on atk and spd. They generally do not want to take hits but could afford to do so when necessary.
brazen atk/spd is on like one seasonal 5* unit... which is definitely why it's not widely used or suggested. Swift sparrow, while 5* locked, it's still much easier to get on multiple units and it doesn't have the HP requirement.
I mean, I fed my only winter robin to Nephenee and I regret nothing, but I think even whales would have a hardish time with that one (especially for competitive arena when every point matters)
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