As of Honkai: Star Rail version 2.3, Firefly and Acheron are widely considered to be the best DPS carry characters in the entire game. However, there must always be a ‘strongest’ character, and between these two, one has to wonder which sits at the mountaintop.
Is Firefly stronger than Acheron in Honkai: Star Rail?
The answer to this very divisive question is actually rather nuanced. Several factors and variables will determine which is the strongest for you. In a vacuum, with both characters sitting at E0, I’d say that Firefly is stronger than Acheron. Allow me to explain my reasoning.
Firefly at E0 has a lot going for her despite her E1 and E2 further boosting her to heavenly heights. She is capable of ridiculous amounts of damage and is very easy to build due to not caring about CRIT-based stats. One key aspect that makes Firefly so powerful is her extreme focus on Break Damage. With such a focal point, Firefly makes use of the best Harmony character in Honkai: Star Rail, Ruan Mei.
However, this is also a key detriment because Firefly must always Break her enemies to be useful in a fight. While few and far between currently, there are scenarios where an enemy(s) can become immune to Breaks. There’s a very real chance these situations can become more common, and if they appear in any of the endgame modes, Firefly will be in a lot of trouble.
At E0, Acheron requires two Nihility teammates to perform at her best. Not only that, but Acheron also wants constant DEF Shred debuffs up on her targets at all times. This makes Nihility characters such Pela and Black Swan her ideal teammates. Her ‘two Nihility’ requirement limits her team composition a lot, but she still has more options than Firefly does. Acheron requires a lot more investment to get going, and it’s often weaker than a mid-level invested Firefly due to her focus being on Break. In most cases, an E0 Acheron will deal less damage than an E0 Firefly if she can Break.
When you start throwing Eidolons into the mix, this is where Acheron improves considerably more in contrast to Firefly, especially in the latter half of the spectrum. Both Firefly and Acheron have extremely powerful E2s that are game-changers, but I’d say that Firefly is still stronger due to her E2 granting her free extra turns. Acheron’s E2 just lessens the Nihility requirement by one, which is a big deal. However, it cannot compete at all with more freebie turns.
At E4, Acheron begins to close the gap due to the increased Ultimate damage she gets. Since her Ultimate is completely reliant on debuff application, is a majority of her damage, and can, therefore, be used very often in normal battle scenarios, we can sort of treat it like her getting extra turns. It still isn’t the same, but it’s worth considering. Firefly’s E4 is nearly useless and does not affect how potent she is. What still puts Firefly ahead of Acheron is her ability to apply Weakness Vulnerability to any foes she is facing. Firefly is always optimal and universal against any enemy for this reason, whereas Acheron is not.
Once Acheron and Firefly reach E6, however, Acheron is the clear winner. Firefly’s E6 greatly boosts her ability to Break enemies, which is fantastic. However, Acheron E6 is among the strongest in all of Honkai: Star Rail. Her E6 makes her a universal DPS like Firefly, allowing her to become optimal against any enemy without having to apply any sort of weakness. Going further beyond, Acheron’s E6 also dramatically boosts the damage of her entire kit by turning it all into Ultimate Damage. This means all of her traces and gear that buff her Ultimate, now buff her entire kit. Firefly does not compete anymore at this point.
In summary, Firefly wins against Acheron until they both reach E6. For the average player, Firefly will do more work, but both characters are still insanely strong and sit at the top of all the others regardless of their Eidolons. You need two teams to conquer Honkai: Star Rail’s endgame, so having them both is nothing short of a boon for your account.