Acheron Guide

Updated for Version 2.3

Note that the information given may change if new discoveries are made. More extensive testing is in progress.

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Introduction

Acheron is a 5* character exclusively obtainable from the ”Words of Yore” Warp in Honkai: Star Rail. As a Lightning-Type damage dealer following the Path of Nihility, she features a unique stacking mechanic replacing Energy for her Ultimate. By utilizing debuffs to charge up her Ultimate, Acheron deals powerful AoE damage, opening up new team archetypes for players.

Infographic

Design: euphorysm | Content: jas

Character Overview

Acheron’s playstyle revolves around her Ultimate, which is the bulk of her damage. It is unique in the fact that it does not charge up using Energy, but with a mechanic called Slashed Dream, obtained through her Skill or by inflicting debuffs on enemies, whether from her allies or enemies themselves. This makes her damage output heavily tied to the rate at which the player can apply debuffs.

Such a heavy focus on debuff application is seen throughout her entire kit, with Acheron’s A4 Bonus Ability giving a damage multiplier based on the number of Nihility characters in the team other than Acheron. This bonus caps out at 2, which can make team composition a daunting task.

All things considered, Acheron’s team composition requirements can appear restrictive, but her unique playstyle, paired with an extremely high damage ceiling, sets her apart as one of the most formidable damage dealers in Honkai: Star Rail.

Playstyles

Hypercarry

Acheron’s playstyle focuses on her Ultimate, carefully timing buffs and debuffs to maximize its damage, and using her teammates to help generate stacks of Slashed Dream. Thanks to Quadrivalent Ascendence, an “overflow” mechanic for Slashed Dream, Acheron can retain overcapped stacks after using her Ultimate, allowing her to delay her Ultimate to better line up with buffs and debuffs.

Acheron’s Ultimate has several key components to it, and understanding each part can help maximize damage. The first part is Rainblade, which are three targetable swings of her Ultimate. Players can select who they attack with Rainblade, and should prioritize selecting enemies with Crimson Knot stacks, as doing so will remove up to 3 stacks and deal AoE damage based on the number of stacks removed. If Acheron hits enemies without Crimson Knot stacks, this detonation will not be triggered. After the three Rainblades, Stygian Resurge is triggered, a large AoE hit that also removes all remaining stacks of Crimson Knot from the field. It is important to note that Crimson Knot stacks removed by Stygian Resurge will NOT deal the AoE damage they would deal if removed by Rainblade. As such, any stacks removed by Stygian Resurge are effectively lost damage potential.

To maximize damage, abilities that apply debuffs should be placed carefully, as these will influence the distribution of Crimson Knots. Ideally, Crimson Knots should be distributed in multiples of 3, as each Rainblade can only remove up to 3 stacks of Crimson Knot.

Traces

Note: Trace levels shown are 1/10/12 (Basic ATK 1/6/7).

Trace Priority

Acheron’s Ultimate constitutes a large portion of her damage, and her Talent provides RES Pen during her Ultimate. Her Skill should not be ignored either, as it can still do a sizable amount of damage and will be used every turn to inflict Slashed Dream. On the other hand, using her Basic ATK should generally be avoided, and it can be left unleveled.

Eidolons

Build

Light Cones

Along the Passing Shore	With both great base stats and beneficial effects, Acheron’s Signature Light Cone is her best option by a wide margin. Mirage Fizzle is always guaranteed to be applied, and will generate one extra stack of Slashed Dream whenever Acheron uses her Basic ATK or Skill. The DMG Boost from Mirage Fizzle is also noticeable as such a large portion of Acheron’s damage is in her Ultimate.
Incessant Rain	A reasonably powerful option if players happen to have it. Stronger than S5 Good Night and Sleep Well, and can apply a debuff to generate additional stacks of Slashed Dream. However, as the debuff is applied after an attack finishes, if all attacked enemies are immediately defeated, no additional stack will be gained.
Patience is All You Need	Surprisingly solid due to the extra Slashed Dream stacks it can provide, along with the other stat bonuses. Note that this debuff can only be inflicted on enemies that do not already have it.
Good Night and Sleep Well	Best 4★ option. Maintaining 3 stacks is trivial in most Acheron teams, and at S3 and above, it is better than S5 Resolution Shines as Pearls of Sweat.
Boundless Choreo	A strong option. It provides a large amount of CRIT, and its secondary effect is easy to activate in Acheron’s teams.
In the Name of the World	Solid base stats make this usable if players already have it. Not worth purchasing solely for Acheron.
Resolution Shines as Pearls of Sweat	The debuff from this Light cone can allow Acheron to use her Ultimate sooner, making it competitive with S3 Good Night Sleep Well. It is imperative that if Acheron is using this Light Cone, no other teammate should also be using a copy of it, as its debuff cannot be reapplied to enemies that are already affected by it.
It’s Showtime	The F2P option. Switch to any of the above if possible.

Relics

Relic Sets

4-Pc Pioneer Diver of Dead Waters	Even without debuffing Light Cones, both the 2-Pc and 4-Pc effect of Pioneer Diver of Dead Waters will be active during Acheron’s Ultimate, as her Talent applies a debuff, making this set her best for her personal damage.
4-Pc Genius of Brilliant Stars	A competitive option unless you reach 100% DEF Shred without this set.
4-Pc Prisoner in Deep Confinement	Potentially better than 4-Pc Genius of Brilliant Stars, provided there are 3 DoT debuffs on an enemy, or 1 DoT against enemies without Quantum Weakness.
4-Pc Band of Sizzling Thunder	Provides a permanent increase to ATK% and DMG%, as Acheron uses her Skill every turn. Usable if you have it, but it is not recommended to farm this for Acheron.
2-Pc Combinations	Combinations of 2-Pc Band of Sizzling Thunder, 2-Pc Pioneer Diver of Dead Waters, 2-Pc Messenger Traversing Hackerspace, 2-Pc Prisoner in Deep Confinement, or 2-Pc Musketeer of Wild Wheat can be used if the above options are not available.

Planar Ornaments

All of these sets are close enough to each other in performance, so choose which set has the better substats.

Izumo Gensei and Takama Divine Realm	As Acheron always wants at least one other Nihility teammate, this Planar set is an easy fit. It grants both ATK% and CRIT Rate, both of which are valuable stats for Acheron.
Inert Salsotto	A very competitive option, as Acheron’s Ultimate makes up a majority of her damage. It is worth mentioning that Inert Salsotto is paired with Belobog of the Architects, which makes farming this set inefficient.
Space Sealing Station	Worth considering if using SPD Boots and none of the above are available. Performs slightly worse than Rutilant Arena if Acheron has less than 120 SPD.
Firmament Frontline: Glamoth	Performs virtually the same as Space Sealing Station at 135 SPD. When choosing between Space Sealing Station and Firmament Frontline: Glamoth, substats will make the largest difference.
Rutilant Arena	The vast majority of Acheron’s damage comes from her Ultimate, although her Skill still contributes some damage, making Rutilant Arena viable if no other set is available.

External SPD buffs can allow Acheron to more easily activate Space Sealing Station and Firmament Frontline: Glamoth Set Effects, and they only have to be activated while Acheron uses her Ultimate.

Stats

Body	Boots	Sphere	Rope
CRIT Rate / CRIT DMG	ATK% ≈ SPD	ATK% > Lightning%	ATK%

Substats

CRIT > ATK% > SPD

The abundance of DMG% in Acheron’s kit means that in many cases, an ATK% Orb is slightly better than a Lightning DMG% Orb. Pick based on your substats.

Acheron is often dependent on her teammates for much of her Slashed Dream stack generation, due to her own debuff application being very limited in comparison. ATK% boots are recommended, but SPD Boots are practically equivalent if she can generate more than one Slashed Dream per turn, whether through her E2 or a debuff-applying Light Cone.

It is recommended to aim for a 1:2 ratio of CRIT Rate to CRIT DMG.

E2 or S1?

Acheron’s E2 has incredible power, as it can enable more team compositions and allow room for more powerful supports, now only requiring 1 Nihility unit to max out the effect of her A4 Bonus Ability. Combined with the extra stack generation on her turns, E2 is a noticeable increase in both power and versatility.

On the flip side, S1 is significantly cheaper with a considerable increase compared to her best non-signature options. In scenarios where Acheron would have the same amount of Ultimates compared to her non-signature options, the damage increase is less noticeable but still significant. Additionally, Acheron is significantly lacking in F2P Light Cone options, and her best 4★ gacha options are still much weaker than her Signature Light Cone.

Character Comparisons

Argenti

Argenti and Acheron are both Ultimate-centric AoE damage dealers. Argenti’s kit is noticeably more tuned towards multi-wave scenarios such as Pure Fiction, while Acheron cares more about her teammates than the number of enemies she is facing.

Jing Yuan

Acheron and Jing Yuan are similar in the fact that they are both AoE Lightning-Type damage dealers. However, Jing Yuan possesses much more wave clearing capability with his AoE Skill and Ultimate, which makes him preferable in scenarios such as Pure Fiction. Acheron also lacks the ability to take advantage of numerous sources of Energy, such as being hit by enemies, defeating enemies, Tingyun’s Ultimate, and various Simulated Universe Blessings.

Notable Synergies

Nihility Units

All Nihility Units carry at least some inherent value by contributing towards Acheron’s A4 Bonus Ability.

Pela	Pela provides SP generation, AoE DEF Shred, and Slashed Dream stack generation with her Ultimate (and Skill at E4 and above). Pela can even generate stacks while staying SP positive by using debuffing Light Cones such as Resolution Shines as Pearls of Sweat. As Resolution Shines as Pearls of Sweat only applies its Ensnared debuff to enemies that do not already have it, if using Pela’s Basic ATK and Ultimate in quick succession, you should use her Basic ATK before her Ultimate, or else she will only generate one stack of Slashed Dream.
Silver Wolf	Silver Wolf’s Talent allows her to consistently generate stacks on every action if she has enough EHR, and her abilities make her perfect for single-target scenarios, especially when paired with another source of DEF Shred such as Pela. Silver Wolf can also enable the Genius of Brilliant Stars set by implanting Quantum Weakness onto enemies, resulting in even more DEF Ignore.
Black Swan	Black Swan is capable of inflicting stacks of Arcana whenever new enemies enter battle, however, this will only generate Crimson Knot if the enemies are summoned through an enemy ability, and not at the start of every wave. She also becomes a more potent support with her E1’s RES Shred. One can also take advantage of Black Swan’s Epiphany debuff, by using Acheron’s Ultimate while it is the target’s turn. Combined with her DEF shred on Skill and her own non-negligible personal damage, Black Swan makes for a surprisingly effective dance partner for Acheron.
Guinaifen	A strong 4★ option if one does not have Silver Wolf. Guinaifen has debuff application and stacking Vulnerability, but can be outclassed by Harmony units such as Sparkle or Bronya.
Welt	Welt can function as a secondary damage dealer at high investment, while also helping to fulfill Acheron’s A4 Bonus Ability. Although he is able to Slow and Imprison enemies, these aspects of his kit do not make him a good sustain, and such a build is dubious at best, especially in non-Imaginary-weak scenarios and without Ruan Mei.

Sustains

Gallagher

Gallagher’s debuffs are sources of extra Slashed Dream and Crimson Knot stacks.

Preservation Units

All Preservation units can hold Trend of the Universal Market, which inflicts debuffs when its wearer is attacked. Each burn debuff application from Trend generates a stack of Slashed Dream and Crimson Knot, at the cost of being unable to control when they are distributed due to random enemy targeting. Gepard and Fire Trailblazer are particularly good for this due to their increased aggro and Taunt respectively.

Harmony Units

Sparkle

Sparkle’s buffs are strong enough to outweigh the fact that she takes up a slot for potential Nihility units. While Silver Wolf performs better in single-target scenarios, Sparkle is noticeably better in AoE. Combined with the extra comfort afforded by her SP generation, Sparkle is a powerful and comfortable support even for E0 Acheron.

Bronya

Much of what applies to Sparkle can be applied to Bronya. Although Bronya has strong buffs on paper, her high SP consumption and short buff durations can lead to awkward scenarios where Acheron gains her Ultimate outside of her turn, and has to choose between delaying it and wasting Slashed Dream stacks, or using it and missing out on Bronya’s buffs. Nonetheless, Bronya is a powerful support and can be an upgrade over some double Nihility team compositions, particularly over Guinaifen.

Teams

Two Nihility Teammates

A hypercarry team that uses two Nihility supports for stack gain as well as to max out Acheron’s A4 Bonus Ability. Ideally, both Nihility units can apply a debuff on every single turn, whether through their kit, or the use of debuffing Light Cones such as Resolution Shines as Pearls of Sweat. Fast Ultimates that apply debuffs are a plus.

Example Teams

This team is strong in single-target scenarios, as Pela and Silver Wolf together can reach 100% DEF Shred on a single enemy. Silver Wolf should use her Basic ATK every turn, only using her Skill to implant Weakness as needed. Pela should use her Basic ATK every turn, only using her Skill when enemies already have ‘Ensnared’ applied to them. Silver Wolf and Pela should distribute their attacks in order to distribute Crimson Knot in multiples of 3.

Silver Wolf, Pela, and Gallagher should all be built with as much SPD as reasonably possible, and can use equipment such as Eagle of Twilight Line, or Multiplication in Gallagher’s case, in order to increase their rate of debuff application.

One Harmony One Nihility

Sacrificing a portion of the multiplier from Acheron’s A4 Bonus Ability, these teams gain the use of powerful Harmony units such as Sparkle or Bronya. While they are fairly competitive and can outperform double Nihility team compositions in AoE scenarios when Acheron is at E0, they are not  outright better until E2 or above.

Example Teams

It is recommended to build a lot of SPD on Sparkle, and use her Skill on Acheron every turn, forgoing SPD on Acheron entirely. Pela should use her Basic ATK every turn, and can delay her Ultimate until after she uses her Basic ATK. If you have Pela’s E4, she can use her Ultimate followed by her Skill to ensure Slashed Dream stacks are generated.

Sustainless

Due to the nature of Acheron’s kit and the amount of power held in her A4 Bonus Ability, Acheron can gain a substantial amount of damage from giving up the sustain slot in her teams. These teams rely on clearing fast, using the incredible power bump to finish fights before enemies are able to deal any meaningful damage to you.

Note that these teams are built mostly for raw damage, and may require resets to work.

Example Teams

This team plays very similarly to the previously mentioned Sparkle and Pela team, substituting the sustain unit for Welt while fulfilling Acheron’s A4 Bonus Ability. Welt functions as a secondary damage dealer in this team, and should not be used purely as a “pseudo-sustain,” as better results would be achieved by using a dedicated sustain character such as Fire Trailblazer.

This is a strong team in Pure Fiction, as Kafka and Black Swan both generate Slashed Dream stacks, while contributing their own damage. Kafka should use her Skill every turn to detonate DoTs, while Black Swan and Ruan Mei should use their Skill to maintain their respective buffs and debuffs, otherwise using their Basic ATK. In Pure Fiction, Acheron does not need to wait for Black Swan’s DEF Shred or Epiphany to clear waves, and should use her Ultimate as soon as it is ready.

Black Swan should be faster than Kafka, in order to apply Arcana before Kafka’s turn. Each of their respective Ultimates can be cast whenever they are ready.

Note that Kafka does not have any notable direct synergy with Acheron and only functions as a debuffer and DoT enabler, and the team will be functionally the same with another DoT unit.

Credits

References

• Acheron Calcs by HunterKee
• Acheron Mastersheet by Bonk

Changelog

• 18 July 2024 – Published for v2.3