The second act of Penacony looms over Honkai: Star Rail with the approach of Version 2.1, which also heralds the arrival of one of Dreamscape’s leading ladies, the deadly Galaxy Ranger Acheron, as a playable unit. Acheron was the first unit confirmed for the Penacony story and she’s been an integral part of the Penacony Trailblaze Mission in Version 2.0. Despite her forgetful nature, Acheron is a being of terrifying destructive might and force, which is perfectly conveyed by her playstyle: as a 5-star Lightning Nihility character, Acheron excels at dealing massive amounts of damage with her unique Ultimate after her enemies are crippled with debuffs.
Here’s how to make the best Acheron build in Honkai: Star Rail. This guide will include a deep dive into Acheron’s kit, as well as how you can maximise her unique Ultimate gains, which 5-star or F2P Light Cones you should be using on her, what order you need to prioritise levelling her Traces, and what team compositions she works best in. If you’re still unsure about whether or not Acheron is right for you, check out our Should You Pull guide for both Acheron and Aventurine here for a bit of aid.
Want more Honkai: Star Rail guides and other content? Then you can find more, including our other 5-star character build guides, here on KeenGamer:
- Honkai: Star Rail Ruan Mei Build Guide
- Honkai: Star Rail | Simulated Universe World 4 Guide (Easy F2P Clear)
- Honkai: Star Rail | Simulated Universe World 6 Guide (Easy F2P Clear)
- Honkai: Star Rail | The Seven Errors of Cycranes Guide
- Honkai: Star Rail | Luminflux Pyxis Day 3 Puzzle Guide
Forgetful, Beautiful
Acheron Ascension Materials
Before we dive into the enigma that is Acheron’s kit and her suite of available abilities, let’s first go over what you’ll need to ascend Acheron and get her to level 80. Reaching maximum Ascension is extremely important with Star Rail characters as, if you don’t, they won’t be able to unlock all of their Traces. In terms of what Acheron needs, you’ll have to grab the following to fully Ascend her:
- 15x Dream Collection Component / 15x Dream Flow Valve / 15x Dream Making Engine (Penacony Enemy Drops)
- 65x Shape Shifter’s Lightning Staff (World Boss Material)
- 308k Credits
Acheron’s first major material is the Dream series of enemy drops. These have a chance of appearing each time you defeat members of the Dreamjolt Troupe within Penacony’s Dreamscape, ranks of which include the mechanical chef t-rex, the Soulcal-loving robot dogs, and the massive automaton monkey. As the name implies, these enemies are most common within hostile areas of the Penacony Dreamscape such as Dream’s Edge so make that your priority target for hunting. However, 2.1 has also added World 9 to the Simulated Universe, another location where you can infinitely farm the Dreamjolt Troupe who spawn there for materials.
As for Acheron’s World Boss Materials, her forgetfulness has gotten the better of her as she needs the Shape Shifter’s Lightning Staff, a Xianzhou Luofu World Boss item. The exact Stagnant Shadow you need to visit is the Shape of Doom in the Stargaze Navalia which has you face off against a Disciple of Saint Santus Medicus Shape Shifter as the main enemy. As such, bring your best Wind, Ice, or Imaginary characters to swiftly conquer this battle.
Finally, Penacony introduced a new Crimson Calyx for Nihility characters in the Alchemy Commission of the Xianzhou Lufou. As a newer Nihility unit, Acheron needs a newer set of materials – the Fiery Spirit, Starfire Essence and Heaven Incinerator – as opposed to the older Obsidian set that Nihility units pre-2.0 required. She’ll need a large quantity of these drops for levelling or unlocking her various Traces, where she’ll also need up to 12 Past Evils of the Borehole Planet Disaster Weekly Boss drops.
Cries in Red
Honkai Star Rail Acheron Kit
Trilateral Wiltcross (Basic ATK)
Next, let’s dig into Acheron’s kit in Honkai: Star Rail to unearth what makes her so unique and such a powerful main DPS. However, that potential isn’t going to come from her Basic ATK, Trilateral Wiltcross, as, like most Nihility units, her other attacking options are much better. Acheron’s Basic ATK simply deals a minor amount of Lightning DMG to a single target.
This attack is simple, basic, and doesn’t tie into any of Acheron’s other abilities. In fact, in prime scenarios, Acheron will never be using her Basic ATK, allowing you to essentially ignore it completely in favour of her Skill or Burst, the two more interesting and lethal aspects of her kit.
Acheron’s Basic ATK
Octobolt Flash (Skill)
As we just mentioned, Acheron’s Skill, Octobolt Flash, is where things start to get more interesting. Once cast, Acheron will lash out with her sword with blistering speed, attacking enemies with a Blast attack which deals Lightning DMG to one main target and then minor Lightning DMG to adjacent targets. Acheron will also inflict the main target of the attack with a special debuff, Crimson Knot, and she’ll gain one stack of Slashed Dream, a buff which is of the utmost importance to Acheron’s overall DPS.
Aside from Breaking targets, Acheron’s Skill is her only consistent way of gaining Slashed Dream stacks which not only shows how important team composition is for her but also how slow her playstyle can be if you don’t properly understand it. We’ll dive into how Slashed Dream stacks work in a moment but, just as an overview, Acheron’s potential and DPS will plummet off a cliff if you cannot gain these stacks quickly, making her Skill a vital part of her kit. Additionally, Octobolt Flash’s multipliers aren’t bad, allowing you to hit some decent damage numbers with it. Always remember, though, that this Skill is more useful as a utility and a buff stacking tool than as a direct form of offence.
Acheron’s Elemental Skill
Slashed Dream Cries in Red (Ultimate)
Acheron’s Ultimate is both the most complex and unique part of her kit and it’s where those Slashed Dream stacks we spoke about previously finally get put into play. Instead of using Energy like most characters in Honkai: Star Rail, Acheron will only be able to cast her Ultimate once you reach 9 stacks of Slashed Dreams. Aside from her Skill, Acheron will also gain a single Slashed Dream stack every time an enemy is afflicted with a debuff, whether that be directly from an ally or from friendly fire like with an Automaton explosion. Both DoT and Break Effects count as debuffs for this effect.
Once Acheron has acquired enough Slashed Dreams, you can unleash her Ultimate, Slashed Dream Cries in Red, which is one of the most powerful and visually striking Ultimates in the game. Upon cast, Acheron will use Rainblade three times, dealing massive Lightning DMG to a single target while still dealing moderate Lightning DMG to all other targets. If the target enemy has any Crimson Knot stacks, Acheron will remove up to three of them, increasing the Rainblade’s DMG for each Knot removed. Then, once she has used Rainblade three times, Acheron will deliver Stygian Resurge, a devastating attack which hits all enemies and removes all remaining stacks of Crimson Knot.
Complicated is the best way to describe Acheron’s Ultimate. Between the unique activation effect and how it locks out meta support units like Huohuo and Tingyun to how her damage drastically increases with each Crimson Knot stack, there’s a lot to keep track of and a lot you need to consider when casting this ability. Most of Acheron’s big damage numbers are going to come from her Ultimate, meaning that you need to get it as quickly as possible, highlighting how important other debuffing teammates are. However, if you can wrap your head around this Ultimate and how to efficiently get it, you’ll have one of Star Rail’s strongest single attacks in the palm of your hand.
Acheron’s Ultimate
Atop Rainleaf Hangs Oneness (Talent)
Acheron’s Talent, Atop Rainleaf Hangs Oneness, is just an extension of her Ultimate. Whenever Acheron reaches 9 stacks of Slashed Dreams, she’s able to use her Ultimate which, according to the Talent, reduces enemy Toughness regardless of Weakness Type and lowers All-Type RES by up to 25% until the end of the Ultimate. Additionally, whenever an ally inflicts a debuff on an opponent, Acheron gains 1 stack of Slashed Dreams and the enemy is afflicted with 1 stack of Crimson Knot.
Most of the important details of the mechanics of Acheron’s Ultimate are buried within her Talent, although the only thing which changes when the Talent is levelled is how much the All-Type RES is lowered. As such, while it’s an extremely vital part of Acheron’s kit, it’s something you don’t have to worry about much. Honestly, the most important part about it is how ally debuffs gives Slashed Dreams to Acheron and Crimson Knot to enemies.
Slashed Dream Stacks
Quadrivalent Ascendance (Technique)
Lastly, the final trick up Acheron’s massive oversized sleeves is her Technique, Quadrivalent Ascendance, which is easily in contention for the best Technique in Honkai: Star Rail. When you use her Technique, Acheron will immediately attack (although she won’t consume SP if you don’t hit an enemy), with the Technique’s effect changing depending on the opponent’s strength. If you attack a normal enemy, they will be defeated instantly.
If, instead, they’re a stronger target, you’ll enter battle and gain the Quadrivalent Ascendance effect at the start of each enemy wave. This deals Lightning DMG to all enemies and reduces their Toughness regardless of Weakness Type, as well as inflicting a random enemy with 1 stack of Crimson Knot and giving Acheron 1 stack of Slashed Dream after she uses her Ultimate.
Just like her Ultimate, Acheron’s Technique is filled to the gills with effects that make it useful in any scenario. Against lower-tier fodder enemies, she can instantly delete them from the game, avoiding battle while still giving you all of the rewards, whether they be materials, Simulated Universe Blessings, or more. On the other hand, against bosses, the menagerie of effects that Quadrivalent Ascendance provides is insane, drastically improving Acheron’s performance in battle. If you have the opportunity to use her Technique, there are very few others you should consider.
Acheron’s Technique
Acheron’s Traces and Passive Abilities
Next, let’s quickly go over Acheron’s suite of passive Traces and stat boosts. Just like the rest of Acheron’s kit, the abilities you can pick up from her Trace Tree are incredibly lethal, improving Acheron’s DMG considerably while also improving her consistency and how quickly she can get back her Ultimate. In short, they’re game-changing and should be a big priority when building her.
Before we go into specific Traces, though, let’s first look at the three major stat boosts Acheron receives from her Trace tree. Honestly, Acheron likely has the best stat boosts in the game with not a single wasted Trace node or stat boost: all of the nodes you can pick up will directly add to her damage output in one way or another. If you manage to pick up all of Acheron’s Traces, she’ll receive the following buffs:
- ATK% Bonus
- Lightning DMG Bonus
- CRIT DMG Bonus
Acheron’s Traces
Acheron’s first major Trace is Red Oni, calling back to her Honkai 3rd doppelganger, and it’s unlocked at Character Ascension 2. When a battle starts, Acheron immediately gains 5 stacks of Slashed Dream and applies 5 stacks of Crimson Knot to a random enemy. Additionally, when Slashed Dream reaches its upper limit of 9, she’ll gain 1 stack of Quadrivalent Ascendance (the buff from her Technique) for every stack which exceeds her limit. The first part of this Trace is incredibly useful as it allows Acheron easier access to her Ultimate at the start of a battle, whereas the second part is a lot more situational but very effective if you can pull it off.
Meanwhile, her second major Trace, The Abyss, unlocks at Character Ascension 4 and impacts Acheron’s team compositions. When there are 1 or 2 other Nihility characters in your party, Acheron’s Basic ATK, Skill and Ultimate DMG increase by 115% and 160%, respectively. You already wanted to Acheron with other debuffers to quickly accumulate her Burst but this Trace just cements Acheron’s reliance on her teammates to succeed. She’s not a solo-carry character and you won’t be able to succeed if you don’t have the right support for her. This Trace is very rewarding while promoting the most effective way to play Acheron.
Lastly, her third major Trace is unlocked at Character Ascension 6 and it’s called Thunder Core. When the Rainblade from Acheron’s Ultimate hits enemy targets with Crimson Knot, her DMG increases by 30%, which stacks up to 3 times 3 turns. Furthermore, when Stygian Resurge triggers, additionally deals Lightning DMG equal to 25% of Acheron’s ATK to a single random enemy six times. This is where Acheron’s most considerable increase in DMG comes from. Honestly, you’ll likely even forget what it does but you’ll certainly see its effects with Acheron’s gigantic damage numbers.
Overall, Acheron’s Traces are a vital part of her character for one reason or another. Some, like Red Oni, are there to improve Acheron’s ease of use and consistency right from the jump, whereas others, like Thunder Core, give Acheron a self-buff that she can use to shred apart her enemies. Her most important Trace is The Abyss as it promotes the best type of team composition for Acheron while rewarding players who follow those guidelines. Acheron is unlike any other DPS in Star Rail, in large part due to her reliance on debuffers compared to buffers, and her Traces make that very clear.
Another Side
Honkai Star Rail Acheron Trace Priority
- Slashed Dream Cries in Red (Ultimate)
- Atop Rainleaf Hangs Oneness (Talent)
- Octobolt Flash (Skill)
- Trilateral Wiltcross (Basic ATK)
The core of Acheron’s entire kit and what she’ll be constantly building to in battle is her Ultimate. Not only is it her main source of damage but it’s also what the majority of her Trace, Eidolon and personal effects revolve around, whether it be Slashed Dreams or Crimson Knot. As such, you’ll want to ensure that this attack is as strong and effective as possible. Investing in this Skill increases the damage of the initial Rainblade attacks, the Stygian Resurge finisher, and even the Crimson Knot DMG multipliers. Acheron is a very rigid character when it comes to builds and her Ultimate will always, no matter what, be the priority.
If Acheron’s Ultimate is the main star, her Talent is the compelling second lead. As the mechanical part of her Ultimate, investing in Atop Rainlead Hangs Oneness will improve Acheron’s damage output by increasing the All-Type RES decrease her Ultimate provides. In short, levelling up Acheron’s Talent is just another way of improving her Ultimate DMG.
The third most important Trace for Acheron is her Skill. As we mentioned earlier, Acheron’s Skill does do good damage but it’s more useful as a utility tool that you will use to quickly gain Slashed Dreams and apply Crimson Knot. Levelling her Skill will only improve its damage, making it a worthwhile investment but not over her Ultimate or her Talent. Then, in dead last, we have Acheron’s Basic ATK which does nothing for her kit and can be safely ignored for the most part.
Red Night, Red Oni
Honkai Star Rail Acheron Eidolons
Whenever you get lucky enough, or unlucky enough, to pull a duplicate of a character you already have in Honkai: Star Rail, you’ll be given that character’s Eidolon. Eidolons allow you to unlock special bonus effects and abilities for the character they belong to, introducing additional, often incredibly powerful, boosts to their main kit. As for Acheron’s Eidolons, she’s a limited 5-star unit so, if you want them, you’ll have to get lucky while her Character Event Warp, Words of Yore, is still active.
- Silenced Sky Spake Sooth: When dealing DMG to debuffed enemies, increases the CRIT Rate by 18%.
- Mute Thunder in Still Tempest: Acheron will only need 1 Nihility character in her team to achieve the 160% ATK bonus from her Trace, The Abyss. Additionally, when this unit’s turn starts, she gains 1 point of Slashed Dream and inflicts 1 stack of Crimson Knot on the enemy with the most Crimson Knot stacks.
- Frost Bites in Death: Ultimate Lv. +2 and Basic ATK Lv. +1.
- Shrined Fire for Mirrored Soul: Whenever enemy targets enter combat, they will be inflicted with Ultimate DMG Vulnerability, increasing the amount of Ultimate DMG they take by 8%.
- Strewn Souls on Erased Earths: Skill Lv. +2 and Talent Lv. +2.
- Apocalypse, the Emancipator: Increases the All-Type RES PEN for Acheron’s Ultimate DMG by 20%. Furthermore, the DMG dealt by her Basic ATK and Skill will also be considered as Ultimate DMG and can reduce enemy Toughness regardless of Weakness Types, triggering the Lightning Weakness Break effect.
Acheron has some of the best Eidolons in the entire game with her E6, in particular, completely transforming her entire kit and potentially power-creeping all of the other DPS units in Star Rail. Aside from that, her E1 and E2 are both relatively low-cost pick-ups that will drastically improve her performance, with the former increasing her reliability and damage output whereas the latter makes her far more consistent while opening up her team composition possibilities.
Patience and Calm
Honkai Star Rail Acheron’s Best Light Cones
Acheron’s Best in Slot: Along the Passing Shore (Nihility)
Acheron’s signature Light Cone, Along the Passing Shore (Path of Nihility), is far and away her best option. You can pick up this Light Cone from the Brilliant Fixation Light Cone Event Warp while Acheron’s own banner, Words of Yore, is still ongoing. As for how it performs, this Light Cone greatly increases Acheron’s damage output by increasing her CRIT DMG and giving her access to a special debuff which deals huge damage.
At level 80, Along the Passing Shore will provide the wearer with 1058 HP, 635 ATK, and 396 DEF along with the Steerer ability. The first effect of Steerer increases the wearer’s CRIT DMG by 36%. Meanwhile, when the wearer hits an enemy target, they will inflict them with Mirage Fizzle for 1 turn. The wearer deals 24% increased DMG to targets inflicted with Mirage Fizzle, with their Ultimate receiving an additional 24% DMG increase against Mirage Fizzle-afflicted enemies.
Acheron’s signature Light Cone is so good for her because it operates on multiple levels to make her stronger, more lethal, and more consistent. Firstly, the huge CRIT DMG and Mirage Fizzle DMG Boost are clear, simple ways of directly improving Acheron’s damage. Secondly, Mirage Fizzle gives Acheron a second debuff which she can inflict on enemies, allowing her to get her Ultimate back at a faster rate, resulting in quicker Ultimates for more sustained damage. Overall, this Light Cone just hones all of Acheron’s edges to a fine, sharp point that she can use to brutalise her opponents.
If you love Acheron and want to spoil her with an incredible Light Cone that will improve all of her capabilities, then open up your wallet and spend some Stellar Jade on Along the Passing Shore. You won’t regret it.
Along the Passing Shore
Recommended 4-Star Light Cones for Acheron
Obviously, that’s easier said than done and whether you’re Stellar Jade funds are wiped out from pulling Acheron herself or whether you’re saving for future characters, many Trailblazers will be on the lookout for replacement Nihility Light Cones for Acheron. While most of Nihility’s character pool relies on DoT effects to sustain themselves, there are a handful of excellent Nihility options that Acheron can make use of in Honkai: Star Rail.
Before we dig any deeper, though, we do need to mention that all of the recommendations are going to be 4 stars because they are far easier to obtain than 5-stars. Currently, the only non-limited 5-star Nihility Light Cone is In the Name of the World. If you do happen to have some other limited Nihility LCs like Patience Is All You Need, give them a spin on Acheron before committing to a lower rarity option.
As for the best replacement Light Cones for Acheron herself, we recommend using Good Night and Sleep Well and Resolution Shines As Pearls of Sweat.
Good Night and Sleep Well
Good Night and Sleep Well is Acheron’s next best in slot after Along the Passing Shore as it’s one of the few Nihility Light Cones which doesn’t revolve around DoT. At max level, this Light Cone provides the wearer with 952 HP, 476 ATK, 330 DEF, as well as the Toiler effect. This effect increases the DMG dealt by the wearer by 12% (24% at R5) for every debuff the target is afflicted with, stacking up to 3 times. Considering that stacking debuffs is the main way to get Acheron’s Ultimate, this is just another boost in damage for an already incredibly strong character.
The other main option for Acheron is another gacha Nihility LC, Resolution Shines As Pearls of Sweat. At level 80, this LC gives the wearer 952 HP, 476 ATK, and 330 DEF. Meanwhile, the Glance Back ability has a 60% (up to 100% at R5) chance to afflict an enemy with Ensnare whenever they are hit by the wearer, which decreases DEF by 12% (16% at R5). In terms of function, this Light Cone serves to give Acheron another debuff that she can apply herself, speeding up the process of earning back her Ultimate without having to rely on her allies as much.
Resolution Shines as Pearls of Sweat
Honkai Star Rail Acheron Best Relics and Planar Ornaments
Relics are second only to Light Cone and team choice in terms of importance when it comes to building a character in Honkai: Star Rail. As a Nihility unit that specialises in raw damage, Acheron actually has a good deal of choice when it comes to set bonuses that she can take advantage of, from Band of Sizzling Thunder to Musketeer of Wild Wheat and more. However, there’s one Relic set and one Planar Ornament set which rules the roost.
When it comes to Acheron’s main Relic set, the best choice is going to be full 4-piece Pioneer Diver of Dead Waters, one of the latest sets added with Penacony. With all four pieces equipped, the wearer will gain 12% increased DMG to enemies with debuffs, a 4% extra CRIT Rate, and either an 8% or 12% extra CRIT DMG bonus against enemies with at least 2 or 3 debuffs, respectively. Furthermore, after the wearer applies a debuff, the aforementioned effects increase by 100% (so a 16% CRIT DMG bonus or a 24% CRIT DMG bonus).
First and foremost, the bonus damage against debuffed targets is incredibly strong and has a lot of uptime because Acheron’s foes will almost always be debuffed anyway. Secondly, as a CRIT scaling DPS, the bonus CRIT Rate and CRIT DMG are both excellent and will only improve her potential even further, allowing Acheron to excel at damage while also taking away some of the RNG required to get exceptional Relics.
Path of Dreamdrive
Meanwhile, for Acheron’s Planar Ornament set, there’s one main set that you cannot ignore. That set is full Izumo Gensei and Takama Divine Realm, one of the new Planar Ornament sets added to the Simulated Universe in 2.1. This set increases the wearer’s ATK by 12% and increases their CRIT Rate by 12% so long as there’s another ally following the same Path as them (so, in Acheron’s case, another Nihility unit).
Thanks to Acheron’s The Abyss Trace, you should always be running her with at least one Nihiltiy character, even if you do have her at E2, meaning that you’ll be easily able to get access to both of these effects. All of Acheron’s DMG scales off of pure ATK whereas the bonus CRIT Rate will make her more reliable and consistent in battle, especially with how many attacks her Ultimate does. When you combine the effects of Divine Realm with that of Diver of Dead Waters, Acheron becomes almost stupidly strong.
Acheron’s Best Relics and Planar Ornaments
Most Important Stats and Substats for Acheron
Relic set bonuses are incredibly important to a character’s build but so are the main stats and substats on those Relics. When it comes to Acheron’s build, she’s a main DPS who specialises in one thing: damage above all else. Additionally, because of her lack of Energy gains, it effectively guts the Energy Recharge stat and makes it useless, turning an otherwise useful bonus into a dead stat. With that in mind, here are the main stats you should be looking for on Acheron’s Relics and Planar Ornaments:
- Body: ATK%
- Feet: ATK% / SPD
- Planar Sphere: Lightning DMG Bonus
- Link Rope: ATK%
As for Acheron’s best substats, they are:
- ATK%
- CRIT Rate
- CRIT DMG
- Break Effect
Flying Goldfish
Honkai Star Rail Acheron Best Team Compositions
Acheron Triple Nihility Team
The best Acheron teams, at least at E0, are going to be those that take great advantage of her Traces and the bonus ATK she gets from running triple Nihility in one team. If you want to take full advantage of that and create a powerful Acheron who sweeps through her opponents, your team should include Acheron, Pela, Welt, and a sustain unit of your choice (preferably Luocha or Fu Xuan).
Honestly, as long as you have two Nihility units in your team, who you choose to put there doesn’t really matter. Every character in the Nihility Path is capable of inflicting some kind of debuff, whether it be a DoT or a stat decrease, and they’re all beneficial to Acheron. Whether it’s Kafka’s ability to be a reliable sub-DPS who still deals big damage while constantly applying Shock or Guinaifen’s ability to Burn and lower DEF at the same time, you should mix and match Nihility units to find your perfect pairing.
Scholarly Pela
However, for this team, we’re recommending Pela and Welt, two of the best Nihility units for maximising Acheron’s Ultimate. Pela’s main utility comes from her Ultimate which deals DEF Down on all targets on the field, making it a great opener for Acheron. Additionally, she can shred shields and enemy buffs and, if you put Resolution Shines on her, she’ll be able to lower DEF with her Basic ATK and Skill, making her even better. As for Welt, his ability to Slow and Imprison gives him two distinct debuffs to trigger for Acheron, as well as making up for her lower SPD without detracting from her raw damage.
Lastly, most Nihility characters are pretty weak and fragile, meaning that you’ll need a sustain of some kind. Like before, who you choose doesn’t really matter as most Abundance or Preservation units serve roughly the same purpose and cannot reliably tap into Acheron’s gameplay. Two who come close are Fu Xuan and Lucoha. The former can soak up damage from the rest of the party while giving them all a lovely CRIT Rate (and CRIT DMG at E1) boost that Acheron will love. On the other hand, Luocha has great damage output, absurd healing, and a lot of potential for Imprisonment.
Acheron Triple Nihility Team
F2P Acheron Team
Of course, not everyone is going to have access to Welt Kafka or Silver Wolf, forcing them to rely on other F2P Nihility units. Well, fortunately, compared to other Paths, Nihility is one of the more F2P-friendly ones in terms of units, likely because it’s also the densest Path in terms of characters. Several events have given out DoT characters for free, making a F2P Acheron team slightly easier than you may think (even if her best pairings are limited 5-stars).
The best F2P Acheron team in Honkai: Star Rail includes March 7th, Guinaifen, and Sampo.
Fire-Bending Guinaifen
This is essentially a stripped-back, F2P version of the triple Nihility team, only with much more focus on DoT as your primary source of debuffs for Acheron. Sampo is your standard Wind Shear applier whose Skill can afflict multiple enemies at once with a powerful DoT, especially when you use his Ultimate to increase DoT DMG. On the other hand, Guinaifen is a lot more interesting as she not only can quickly apply Burn with any of her abilities, but her Firekiss debuff lowers enemy DEF, allowing Acheron to deal even more damage to her targets.
Meanwhile, our main sustain in this team is going to be March 7th for one main reason: her Ultimate and Follow-Up Attack have the potential to Freeze which counts as another debuff for Acheron. While this does put the team in slightly riskier territory – especially with how squishy all the Nihilty units are – it does allow you to maintain high DPS and have a reliable sustain unit that can draw aggro, keep you alive, and still contribute to Acheron’s big Ultimate damage.
F2P Acheron Team
That was how to make the best Acheron build and team in Honkai: Star Rail.
