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Honkai Star Rail’s Firefly build

Honkai Star Rail’s Firefly is poised and ready to light up our battlefields, so here's her best build, light cones, relics, and more.

Honkai Star Rail's Firefly in a flight suit like she's in Evangelion, taken from the teaser image for her Myriad Celestia trailer

Honkai Star Rail’s Firefly has made quite the splash in Penacony’s story so far, and the twists and turns just keep on coming with her imminent release as a playable character. Fair warning, this guide contains spoilers about Firefly’s identity, so make sure you’re all caught up before continuing.

Whether you’ve just stepped aboard the Astral Express or you’re a seasoned Trailblazer, make sure you check out our Honkai Star Rail tier list, Honkai Star Rail events guide, and Honkai Star Rail codes guide. Alternatively, take a trip to Teyvat with our build guides for Genshin Impact’s Venti, Genshin Impact’s Albedo, and Genshin Impact’s Razor.

Here’s everything we know about Honkai Star Rail’s Firefly.

What is the best Honkai Star Rail Firefly build?

Best light cone Whereabouts Should Dreams Rest
Alternative light cone On the Fall of an Aeon, Indelible Promise
Best relic set Iron Cavalry Against the Scourge
Best planar ornament set Forge of the Kalpagni Lantern
Main stats
  • Body: attack%
  • Feet: speed
  • Planar sphere: attack%
  • Link rope: break effect
  • Speed
  • Break effect
  • Attack%

Firefly’s best light cone is her signature five-star cone, Whereabouts Should Dreams Rest. Her best relic combination is four pieces of Iron Cavalry Against the Scourge and two pieces of Forge of the Kalpagni Lantern. You should prioritize attack%, speed, and break effect on your relics for the best outcome.

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How should I use Firefly?

Firefly, or SAM as she’s known in battle, is a five-star fire character who walks the path of Destruction. This means she excels at surviving for her teammates and dishing out lots of single-target and multi-target damage.

Firefly’s kit revolves around her ultimate, which enhances her basic attack and skill, while also adding fire weakness to her enemies. Transform as soon as possible in battles to make the most of SAM’s increased break ability and damage.

What are the best light cones for Firefly?

As a limited five-star character, Firefly’s best light cone is Whereabouts Should Dreams Rest, which is her signature light cone. Its ability synergizes with her break damage-focused build, making it the perfect companion for her kit, even at superimposition one.

Of course, both Firefly and her light cone are on limited banners, so getting your hands on both might be tough. On the Fall of an Aeon is a great five-star alternative as you can purchase it rather than relying on gacha luck, or Indelible Promise is a good four-star backup option.

Light cone Effect How to obtain
Whereabouts Should Dreams Rest Increases Firefly’s break effect by 60%. When she deals break damage to an enemy target, inflict Routed on the enemy, lasting for two turns. Targets afflicted with Routed receive 24% increased break damage from Firefly, and their speed is lowered by 20%. Effects of a similar type cannot stack Event light cone warp
On the Fall of an Aeon Whenever Firefly attacks, her attack increases by 8% in this battle. This effect can stack up to four times. After a character inflicts weakness break on an enemy, Firefly’s damage increases by 12% for two turns Herta’s Store
Indelible Promise Increases Firefly’s break effect by 28%. When she uses her ultimate, Firefly’s crit rate increases by 15%, lasting for two turns Gacha

What are the best relics for Firefly?

Firefly’s kit synergizes with the new cavern relic set Iron Cavalry Against the Scourge thanks to its focus on both break effect and super break effect, the new status added alongside Honkai Star Rail’s Trailblazer‘s Harmony kit. As long as you focus on her break effect, you’ll have no trouble meeting the set’s buff requirements. If you’re looking for a cheaper option, try out a four-piece set of Thief of Shooting Meteor, or mix two pieces of Thief with Messanger Traversing Hackerspace for a classic catch-all break effect and speed buff.

As for planar ornaments, Firefly’s best-in-slot set is Forge of the Kalpagni Lantern. Her ability to apply fire weakness to enemies means she can always activate its break effect buff. If you’re struggling with the divergent universe, Talia: Kingdom of Banditry is a decent alternative.

Relic set Effect How to obtain
Iron Cavalry Against the Scourge Two pieces equipped: increases break effect by 16%
Four pieces equipped: if Firefly’s break effect is 150% or higher, ignore 10% of the enemy target’s defense when dealing break damage to them. When Firefly’s break effect is 250% or higher, the Super Break damage she deals to enemy targets additionally ignores 15% of the targets’ defense
Cavern of Corrosion: Path of Cavalier in the Penacony Grand Theater
Thief of Shooting Meteor Two pieces equipped: increases break effect by 16%
Four pieces equipped: increases Firefly’s break effect by 16%. When she inflicts weakness break on an enemy, regenerate three energy
Cavern of Corrosion: Path of Jabbing Punch in Jarilo-VI’s Silvermane Guard Restricted Zone
Messenger Traversing Hackerspace Two pieces equipped: increases speed by 6%
Four pieces equipped: not applicable
Cavern of Corrosion: Path of Elixir Seekers in the Xianzhou Luofu’s Alchemy Commission

Planar ornaments

Relic set Effect How to obtain
Forge of the Kalpagni Lantern Two pieces equipped: increases Firefly’s speed by 6%. When she hits enemy targets with fire weakness, Firefly’s break effect increases by 40%, lasting for one turn Divergent Universe rewards
Talia: Kingdom of Banditry Two pieces equipped:  increases Firefly’s break effect by 16%. When her speed reaches 145 or higher, Firefly’s break effect increases by an extra 20% Immersion Reward devices in World 4 of the Simulated Universe

Relic stat recommendations

Main stats:

  • Body: attack%
  • Feet: speed
  • Planar sphere: attack%
  • Link rope: break effect


  • Speed
  • Break effect
  • Attack%

What’s the best Firefly team comp?

We’re still getting to grips with Firefly’s kit and synergies, but we know for sure that she and the Harmony Trailblazer are a match made in heaven, thanks to Super Break. Firefly’s fire weakness application also makes Honkai Star Rail’s Gallagher a viable support pick as you can also use him to deal damage while you’re charging up his skill.

Here’s an example of a strong, F2P-friendly Firefly team comp:

Main DPS Support Support Healer
HSR Firefly iconFirefly HSR Harmony TrailblazerTrailblazer (Harmony) Honkai Star Rail Pela iconPela HSR Gallagher iconGallagher

Firefly checking her hair

What are Firefly’s abilities?

Firefly’s ultimate enhances her basic attack and skill, so we’ve listed both versions below.

Active skills:

Skill Effect
Basic attack: Order: Flare Propulsion Firefly deals fire damage equal to 50% of her attack to a single target enemy
Enhanced basic attack: Fyrefly Type-IV: Pyrogenic Decimation Restores HP equal to 20% of Firefly’s max HP. Deals fire damage equal to 100% of her attack to a single target enemy
Skill: Order: Aerial Bombardment Consumes HP equal to 40% of Firefly’s max HP and regenerates a fixed amount of energy equal to 50% of her max energy. Deals fire damage equal to 100% of Firefly’s attack to a single target enemy. If the current HP is not sufficient, this skill reduces Firefly’s HP to one when used. Advances her next action by 25%
Enhanced skill: Fyrefly Type-IV: Deathstar Overload Restores HP by an amount equal to 25% of Firefly’s max HP. Applies fire weakness to a single target enemy, lasting for two turns. Deals fire damage equal to (0.2 x break effect x 100%) of Firefly’s attack to this target. At the same time, deal fire damage equal to (0.1 x break effect x 50%) of Firefly’s attack to adjacent targets. The break effect in this calculation caps at 360%
Ultimate: Fyrefly Type-IV: Complete Combustion Enters the Complete Combustion state, advancing Firefly’s action by 100% and enhancing her basic attack and skill. While in this state, her speed increases by 30, her weakness break efficiency increases by 50%, and her break damage increases by 10% until the end of the current attack. A countdown starts on the Complete Combustion state and Firefly cannot use her ult again while in this state

Passive skill: 

Skill Effect
Talent: Chrysalid Pyronexus The lower the HP, the less damage Firefly receives. When her HP is 20% or lower, her damage reduction reaches its maximum effect, reducing up to 20%. During Compete Combustion, her damage reduction remains at maximum effect and her effect resistance increases by 10%. If Firefly’s energy is lower than 50% when the battle starts, she regenerates energy to 50%. Regenerating her energy to maximum dispels all debuffs on Firefly.


Technique Effect
Δ Order: Meteoric Incineration Firefly leaps into the air and moves around freely for five seconds, which can end early by launching a plunging attack. When the technique ends, Firefly plunges and immediately attacks all enemies within a set area. At the start of each wave, Firefly applies fire weakness to all enemies that lasts for two turns. Then, she deals fire damage equal to 200% of  her attack to all enemies


Trace Effect
Module α: Antilag Outburst During Complete Combustion, attacking enemies that have no fire weakness can also reduce their toughness by a number equivalent to 55% of the original toughness reduction from Firefly’s abilities
Module γ: Core Overload For ever ten points of Firefly’s attack that exceeds 1.8k, her break effect increases by 0.8%
Module β: Autoreactive Armor When Firefly is in Complete Combustion and her break effect is equal to or greater than 200%/360%, attacking a weakness-broken enemy converts the toughness reduction of this attack into one instance of 35%/50% Super Break damage

What are Firefly’s eidolons?

If you’re lucky enough to pull multiple copies of Firefly, here are the bonuses that you can unlock.

Eidolon Effect
In Reddened Chrysalis, I Once Rest When using her enhanced skill, Firefly ignores 15% of the target’s defense. The enhanced skill does not consume skill points
From Shattered Sky, I Free Fall While in Complete Combustion mode, using the enhanced basic attack or the enhanced skill to defeat an enemy target or to break their weakness lets Firefly immediately gain an extra turn. This can trigger again after one turn
Amidst Silenced Stars, I Deep Sleep Raises Firefly’s skill level by two, up to a maximum of level 15, and her basic attack level by one, up to a maximum of level ten
Upon Lighted Fyrefly, I Soon Gaze While in Complete Combustion mode, Firefly’s effect resistance increases by 50%
From Undreamt Night, I Thence Shine Raises Firefly’s ultimate level by two, up to a maximum of level 15, and her talent level by two, up to a maximum of level 15
In Finalized Morrow, I Full Bloom While in Complete Combustion mode, Firefly’s fire resistance penetration increases by 20%. When she uses the enhanced basic attack or skill, her weakness break efficiency increases by 50%

honkai star rail firefly in a trailer with a green shade over her

What are Firefly’s ascension materials?

As well as needing EXP logs to level up Firefly, you also need a set of unique materials to ascend her at certain intervals.

Here are all of the materials you need to fully ascend Firefly:

Required level Credits Ascension materials
20 4k Five tatters of thought
30 8k Ten tatters of thought
40 16k Three raging hearts and six fragments of impression
50 40k Seven raging hearts and nine fragments of impression
60 80k 20 raging hearts and six shards of desires
70 160k 35 raging hearts and nine shards of desires

Here’s where to get all of Firefly’s ascension materials:

  • Tatters of thought / fragments of impression / shards of desires – drops from memory zone meme enemies in either Penacony’s Dreamscape or the Honkai Star Rail simulated universe, from assignment rewards, via synthesis, or the embers exchange store
  • Raging hearts – drops from the Stagnant Shadow: Shape of Ire in  Penacony’s Dewlight Pavilion

What are Firefly’s trace materials?

Firefly’s traces let you individually upgrade her attacks and other abilities. Here are all of Firefly’s trace materials:

  • 41 tatters of thought, 56 fragments of impression, and 58 shards of desires
    • Obtain from drops from memory zone meme enemies in either Penacony’s Dreamscape or the Honkai Star Rail simulated universe, from assignment rewards, via synthesis, or the embers exchange store
  • 15 borisin teeth, 72 lupitoxin sawteeth, and 139 moon madness fangs
    • Rewards from the Crimson Calyx: Bud of Destruction in Scalegorge Waterscape, purchasable from the embers exchange, or crafted via synthesis
  • 12 lost echoes of the shared wish – rewards from the Echo of War: Salutations of Ashen Dreams
  • 11 tracks of destiny
  • Three million credits

Skill trace priority:

  • Ultimate > Skill > Talent > Basic attack

Major trace priority:

  • Module α: Antilag Outburst = Module β: Autoreactive Armor > Module γ: Core Overload

That’s everything we know about Honkai Star Rail’s Firefly so far. While you’re here, check out our guides to other intriguing characters like Honkai Star Rail’s Black Swan, Honkai Star Rail’s Jing Yuan, and Honkai Star Rail’s Lynx. We also have a Zenless Zone Zero preview you get you excited for Hoyoverse’s newest adventure.