Honkai: Star RailBlack SwanBest build, teams and other guides

Black Swan is a complex but powerful DoT character. She has a stackable DoT effect that can spread itself to adjacent targets and deal good amounts of damage outside of her turn. With enough stacks, this DoT will also ignore a portion of the affected enemies’ DEF. Black Swan can also further reduce enemy DEF with her Skill, and increase enemy vulnerability with her Ultimate, the latter providing greater opportunities to stack her powerful DoT further by preventing its falloff for one turn.

At last, the mysterious figure we first saw in the Fables About the Stars is finally here. Look, I’ll start by saying that this is one of the most complex dps characters we’ve gotten thus far, so I will do my best to explain exactly how she works and why she’s so terrifying. This is easily the longest review to date, and I hope you’ll forgive me for making you read this much.

Black Swan’s entire kit revolves around her Talent and its associated debuff called Arcana, and it’s all rather verbose. Arcana is a debuff that deals Damage over Time (DoT) but it has a certain interaction I’ll explain later. Just keep this in mind. Enemies afflicted by Arcana will receive Wind DoT at the start of their turn, up to 240% ATK. Each stack of Arcana increases this multiplier by 12%, meaning this starts to scale very quickly. Then, after the enemy receives the damage from Arcana, the Arcana stacks reset to 1. Arcana can stack up to 50 times. If you’re interested to know how much a 50-stacked Arcana proc does, it’s 840% ATK. That’s an Argenti Ultimate. It’s an Argenti Ultimate. It’s unlikely you’ll get to 50 outside of Simulated Universe or without her E6, but you can still get quite high stacks if you know what you’re doing.

Arcana gains stacks through multiple ways, including Black Swan’s Skill and Basic ATK, but there is another part to her Talent first. Every time an enemy receives DoT at the start of their turn, there is a 65% base chance to apply another stack of Arcana. This includes all forms of DoT including Arcana itself. It doesn’t look like it does because the damage happens so quickly but it actually does count itself before it applies the damage and resets to 1. This applies to other character’s DoT effects, Light Cone DoT effects, and even Break DoT.

So here’s how it is; Arcana gains stacks whenever enemies receive DoT damage on their turn, with each stack adding onto the original damage multiplier. Arcana then deals its damage and resets its stacks to 1. Until you unlock a later Bonus Ability Trace, Arcana will only be stacked by Black Swan’s Skill and Basic ATK, and by the enemy taking DoT damage on their turn. Arcana resetting to 1 after the enemy’s turn also means that this is the first DoT effect that lasts indefinitely, so once it’s been applied, that enemy is guaranteed to suffer.

Aside from the increased multiplier, extra stacks gain bonus effects at certain milestones; at 3 Arcana stacks, the expiration of Arcana will additionally deal 180% ATK to adjacent targets with a 65% base chance of applying 1 stack of Arcana to said adjacent targets. This is how Arcana can spread stacks to other foes. This is also the first DoT effect in the game that can hit more than one enemy at a time, and it’s a part of how Black Swan’s AoE damage reaches highly competitive amounts.

At 7 stacks of Arcana, the current DoT will ignore 20% of the main target’s as well as adjacent foes’ DEF, leading to even more ridiculous damage spikes. A well-formed team including at least one other DoT character will generally have no issues reaching this amount on tougher foes, but if you’re ever using Black Swan by herself, you may find it happening less frequently.

Okay, that’s the Talent, whew. Black Swan’s Skill deals up to 90% ATK to a single enemy and adjacent foes. It also has a 100% base chance to apply 1 stack of Arcana to all targets hit. There is also a 100% base chance to reduce the DEF of targets hit by up to 20.8% for 3 whole turns. That’s a lot for only one Skill. As a Blast AoE, it also deals increased Toughness damage against the main target. This Skill is an easy way to start the Arcana stacking. The DEF Shred is also incredibly powerful, especially since DoT characters have such easy access to DEF ignore with the Prisoner in Deep Confinement Relic Set. This is your daily reminder that DEF Shred only gets better the more of it you have.

Black Swan’s Basic ATK is quite unique as it is one of the only non-Enhanced Basic ATKs to have additional functionality. It deals up to 60% ATK to a single target and has a 65% base chance of applying 1 stack of Arcana to the attacked enemy. This means Swan can stack Arcana without even consuming SP in single-target scenarios, making her quite SP-positive in between reapplying the DEF Shred from her Skill.

In addition to this, Swan’s Basic ATK also has the following effect: if the attacked enemy is suffering from Wind Shear, Bleed, Burn, or Shock, then there is a 65% base chance of applying 1 extra stack of Arcana for each type of DoT debuff on the target. This allows Swan to tactically use her Basic ATK on specific enemies to add a large number of Arcana stacks in a single action without expending a single Skill Point, potentially landing her an extra 5 stacks. But it’s probably unlikely to have that many DoT effects on an enemy… Unless…

Finally, we arrive at the Ultimate. This ability visually is just wild, and its effects are similarly insane. Black Swan’s Ultimate deals up to 120% ATK to all enemies on the field and applies a debuff called Epiphany for 2 turns. Epiphany increases enemy DMG taken by 25% during their turn specifically, and additionally makes Arcana count as Wind Shear, Bleed, Burn, and Shock effects. Enemies afflicted by Epiphany will also not automatically reset the stacks of Arcana on their turn, and this non-reset effect can happen 1 time between reapplications.

Now of course, upon reading this you may think that the 1 time non-reset for Arcana is the big draw — and you’re right — but this line about Arcana counting as all four DoT effects simultaneously means a couple of things; firstly is that now any DoT teammates with forced DoT procs can now detonate Arcana with their own abilities; and secondly, Black Swan can now turbo stack Arcana by herself with her Basic ATK.

With her Ultimate, Swan doesn’t need the other DoT effects to actually be applied in order to make use of the extra functionality on her Basic ATK. It actually makes it very easy to get 2 uses out of a 7+ stacked Arcana with the full DEF ignore effect. Keep in mind that if enemies die before Arcana can trigger, it will not propagate, even if you have the required number of stacks - but while this was a big issue back in the day when Black Swan first released, nowadays the HP of enemies is way higher so you don't have to worry about it that much. With her Ultimate only having a cost of 120 Energy, it’ll actually be up fairly frequently, especially if Swan is the one getting the killing blows.

Black Swan’s Bonus Ability Traces heavily benefit her gameplay. Her A6 is of the same vein as Xueyi’s A2, only for Effect Hit Rate instead of Break Effect; Black Swan gets bonus permanent DMG% based on how much Effect Hit Rate (EHR) she has, transferring 60% of EHR into DMG%, up to a cap of 72%. This means Black Swan will have this maximum bonus at 120% EHR. That’s a lot of EHR, but given Swan’s low base chances for Arcana, this actually helps reimburse the damage you lose from not having as much ATK as you normally would for a DoT unit.

A2 gives Black Swan’s Skill the same additional functionality that her Basic ATK has, namely the ability to proc extra stacks of Arcana on enemies with any of the four standard DoT effects, meaning her Skill can now also turbo stack Arcana during her Ultimate’s Epiphany effect, as well as benefiting from any DoT effects from allies. The other big benefit of this is that the Skill is of course a Blast AoE meaning it’s much easier to stack in AoE content, and using her Skill means more Energy back than a Basic ATK, leading to further increased Ultimate uptime. Do note that the extra stacking will only work against the primary target of the Blast AoE.

A4 also helps rack up Arcana stacks through ally-forced DoT detonations, having a 65% base chance of stacking 1 Arcana up to 3 times in a single attack. Anything that forces Arcana to proc will also count for this limit, but it does not specifically need to be Arcana that is detonated. This is beneficial for pretty much all other DoT units, such as Kafka, Sampo, Guinaifen, and even Luka.

You don’t need her Eidolons, they’re redundant. There’s already nothing that can endure Black Swan’s damage, who are you trying to kill here? God? Well with her Eidolons you may very well be able to do that, just like in a classic JRPG. Actually maybe she can already do that… Insert Trailblazer speech about choices here.

Okay that’s the kit broken down, and it’s a lot, but it’s actually not too bad once you’ve tinkered with it a little. All you’re doing is stacking Arcana as much as you can and using the Ultimate to facilitate this when possible. Ideally you’re getting 7 or more stacks before the enemy’s turn, but as long as you’re getting enough for the number of enemies you’re fighting, you’ll be just fine. It’s definitely easier said than done, however. Pairing Black Swan with at least one other DoT teammate will expedite the stacking of Arcana.

Kafka is of course the first one to come to mind, and it should surprise nobody to hear that she is Black Swan’s best teammate. Kafka being able to detonate DoT effects with both her Skill and her Ultimate means that stacking Arcana is really not very challenging at all, and that’s just at base; if your Kafka has her signature Light Cone, that counts as an extra DoT for the purposes of Black Swan’s A4, so it’s even better but by no means a necessity. They both work extremely well with each other and due to the ease of access of DEF Shred and DEF ignore for both DoT units and Nihility units, coupled with Black Swan’s inherent DEF ignore, this makes for an extremely powerful team that has no trouble killing pretty much everything in the game.

As a pair for Kafka, Black Swan is going to be compared to everyone’s favourite Sampo Koski due to them both being Wind Nihility DoT units. I am a big Sampo shill, you’ll know this if you read his review. He has exactly two things going for him, and that is superior Breaking and vastly superior ease of use. That’s it. In all other aspects, Black Swan absolutely trounces Sampo. You know it’s true when I’m telling you this. Sampo is still more than capable in his own right and the bar he sets is already fairly high… Black Swan is just better. 

She does work pretty well in a team with Sampo though, especially if Sampo is at or above E4. In single-target scenarios, Sampo plus Swan is actually somewhat competitive with Kafka plus Swan, though this starts to fall behind the latter in AoE scenarios. Sampo is also a lot easier to pick up and play, and has superior Breaking, so there are still cases where you may want to use him. Just please remember that both Sampo and Swan need a minimum ramp-up time in combat, even if Swan can lead with 1 stack of Arcana.

It should be noted that Black Swan does not technically need DoT teammates to deal damage, but by omitting another DoT unit from the team, Black Swan cares far more about her Ultimate and its uptime, meaning you will need to facilitate as much Energy for her as possible if you choose to go this route. Hear this, it is generally not worth it to use Swan as a hypercarry — not necessarily  because she’s bad at it, but because it just wholly squanders her potential. Just use her properly, it’s ironically less of a headache.

Black Swan is also usable as a damage-support hybrid due to the DEF Shred on her Skill. It’s not really the recommended way of using her but you definitely can do that, I guess. Nihility is a path that doesn’t care about rules anyway, so you can always just slap on Resolution Shines as Pearls of Sweat and have even more DEF reduction on your Black Swan, or just go the standard damage route and make up the difference that way. While she doesn’t have quite as much damage amplification as other supports, she does have formidable personal damage, so… do with this information what you will. This playstyle can become even more potent with her E1, but it is not necessary for her to be used in this way.

Keep in mind that if you want to bring the absolute most out of Black Swan, you should be playing her in a DoT team with other DoT characters. Swan at her max is overkill, but if you truly want to min-max, this is the way you reach that height. Comparing her support hybrid playstyle to the DoT team playstyle is like comparing gold to platinum; they’re both amazing, but one is still notably more coveted.

The first real issue is that Black Swan takes the crown away from Xueyi for ‘most ridiculous investment floor requirement’. With all of Swan’s important Arcana-related effects being stuck at a 65% base chance to occur, you are going to need an exorbitant amount of Effect Hit Rate, upwards of 120%. Due to the importance and power of Arcana stacks, as well as Black Swan’s A6 giving DMG% for EHR, you are highly incentivized to go for this.

You want all of this plus the usual affair for DoT characters of high SPD and high ATK. Her signature Light Cone alleviates this investment requirement, but she doesn't need her signature Light Cone in any way, and she is evaluated as if she does not have it. Even if it is complete overkill — and it is—, it may be something you consider going for to even further bolster this character for the future. Luckily for us all, Nihility Light Cones are just built different, and you are not lacking for good and even competitive accessible choices. All you’ll need to do is factor in the stats you’re missing and go from there.

The second issue is that Black Swan is a complex character. If you’ve made it this far in the review, I shouldn’t really need to tell you this, but it does highlight that making the most out of Black Swan relies on you having a very clear understanding of what everything in her kit does and how it interacts with other things, because it could be the difference between a big brain play that wipes the field, or a small brain play that leaves the enemy alive and very angry. This is the ‘Skill issue’ issue, but it’s honestly not too difficult to overcome by just playing Swan; sometimes you may need to hold her Ultimate to hit a fresh wave or to turbo stack Arcana on Elites or Bosses, and sometimes you may need to change your primary target to better propagate Arcana. You will naturally get a feel for how she works over time.

While back in the day, Black Swan together with Kafka formed one of the strongest duos in the game, nowadays they struggle. A lot. The main issue behind the decline is the lack of Harmony characters that can amplify the DoT playstyle - while every other archetype (Break, FUA, Hypercarry) received new toys that make the damage dealers of that playstyle stronger, DoT lie forgotten. Hopefully, this will change one day, but till it happens, Black Swan and Kafka will be used primarily in Pure Fiction where the format still works well for their strengths.