Fire

Destruction

Firefly

Member of the Stellaron Hunters

TierSS

RolesMain DPS · Break

Release2.3

Firefly is a Fire Destruction Super Break damage dealer. Her Skill burns her own HP to refill 60% of her Energy, and her Ultimate turns her into SAM's Complete Combustion state: +60 SPD, a 100% action advance and Enhanced attacks that heal her, implant Fire Weakness on several enemies and turn Toughness damage into massive Super Break DMG. Buffed in version 4.2, she is back at the top of Memory of Chaos alongside The Dahlia and Fugue.

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Super Break DPS

Light Cones

Whereabouts Should Dreams Rest BiS

5★

Signature and best in slot: +60% Break Effect and Routed, which makes enemies take 24% more Break DMG from her.

Break Effect +60%; Break DMG inflicts Routed, making the enemy take 24% more Break DMG from the wearer and lose 20% SPD.

Thus Burns the Dawn

5★

Phainon's signature is a great alternative: +12 base SPD, the highest base ATK in the game (converted into Break Effect by her A6) and 18% DEF ignore that also applies to Break DMG. Don't push total DEF reduction past 100%.

Base SPD +12 and ignores 18% DEF; after the Ultimate, DMG +60% until the start of the next turn.

On the Fall of an Aeon

5★

Best free option (5★ from Herta's Store, S5 with custom superimposers): lots of ATK, which her A6 turns into Break Effect.

Each attack grants +8% ATK for the battle (up to 4 stacks), and breaking a Weakness grants +12% DMG for 2 turns.

Indelible Promise

4★

4★ option: Break Effect, plus CRIT Rate after her Ultimate. Stronger at high Superimposition.

Break Effect +28%, and CRIT Rate +15% for 2 turns after using the Ultimate.

Relics

Iron Cavalry Against the Scourge ×4

Best in slot by a wide margin: Break Effect, and her Break and Super Break DMG ignore up to 25% DEF.

Set effects

2pIncreases Break Effect by 16%.

4pIf the wearer's Break Effect is 150% or higher, the Break DMG dealt to the enemy target ignores 10% of their DEF. If the wearer's Break Effect is 250% or higher, the Super Break DMG dealt to the enemy target additionally ignores 15% of their DEF.

Thief of Shooting Meteor ×4

Much weaker alternative: Break Effect and Energy on Weakness Break.

Set effects

2pIncreases Break Effect by 16%.

4pIncreases the wearer's Break Effect by 16%. After the wearer inflicts Weakness Break on an enemy, regenerates 3 Energy.

Thief of Shooting Meteor ×2

Messenger Traversing Hackerspace ×2

Break Effect and SPD if your 4-piece pieces have poor substats.

Set effects

2pIncreases Break Effect by 16%.

2pIncreases SPD by 6%.

Planar ornaments

Forge of the Kalpagni Lantern ×2

Best in slot: SPD, and +40% Break Effect against Fire-weak enemies — which she creates herself.

Set effects

2pIncreases the wearer's SPD by 6%. When the wearer hits an enemy target that has Fire Weakness, the wearer's Break Effect increases by 40%, lasting for 1 turn(s).

Talia: Kingdom of Banditry ×2

Similar Break Effect at 145 SPD but no SPD bonus: fine if your SPD is already covered.

Set effects

2pIncreases the wearer's Break Effect by 16%. When the wearer's SPD reaches 145 or higher, the wearer's Break Effect increases by an extra 20%.

Space Sealing Station ×2

ATK that her A6 converts into Break Effect.

Set effects

2pIncreases the wearer's ATK by 12%. When the wearer's SPD reaches 120 or higher, the wearer's ATK increases by an extra 12%.

Main stats

Body

ATK%

Feet

SPD

Planar Sphere

ATK%

Link Rope

Break Effect

Substat priority

1SPD 2Break Effect 3ATK% 4ATK

Stat targets

SPD: 150–157 before combat (Prydwen recommends 157, or 178.4 in Memory of Chaos; Game8: 150, about 164 with Ruan Mei, 178–188 with The Dahlia)
Break Effect: 300%+ in combat (unlocks A4's 150% Super Break); her Enhanced Skill's damage only counts up to 360%
ATK: 1,800+ for her A6, about 2,600+ recommended

Talent priority

Ultimate

Skill

Talent

Basic ATK

Major Trace priority: Module α: Antilag Outburst (A2) > Module β: Autoreactive Armor (A4) > Module γ: Core Overload (A6).

Teams

Recommended teams

Premium Super Break

Firefly

Fugue

The Dahlia

Lingsha

Her most used team. The Dahlia lets her deal Super Break DMG to enemies that aren't broken yet, restores Skill Points and Energy and speeds her up; Fugue adds Break Effect and extra Toughness; Lingsha heals and makes enemies take more Break DMG.

Sustain-less

Firefly

Fugue

Ruan Mei

The Dahlia

Firefly's own durability lets you swap the healer for Ruan Mei: more Weakness Break Efficiency, RES PEN and longer Break windows.

Accessible

Firefly

Trailblazer (Harmony)

The Dahlia

Gallagher

The free Trailblazer (Harmony) boosts Super Break, and Gallagher heals, generates Skill Points and applies Besotted. Keep The Dahlia first: without her, Super Break struggles today.

Guide

How to play

How she works

Order: Aerial Bombardment (Skill). Consumes 40% of her Max HP to regenerate 60% of her Max Energy and advances her next action by 25%. She starts every battle with at least 50% Energy, so one Skill is enough to reach her 240-Energy Ultimate.
Complete Combustion (Ultimate). A 100% action advance, +60 SPD, and Enhanced Basic ATK and Skill that get +50% Weakness Break Efficiency and deal +20% Break DMG. The state ends when its countdown (fixed SPD 70) reaches its turn, and she can't recast her Ultimate until then.
Deathstar Overload (Enhanced Skill). Heals her for 25% of her Max HP and implants Fire Weakness on the target and adjacent enemies for 2 turns (since version 4.2), which also keeps Forge of the Kalpagni Lantern active.
Module β: Autoreactive Armor (A4). In Complete Combustion, with 150%/300% Break Effect, her attacks against Weakness-Broken enemies turn their Toughness reduction into 100%/150% Super Break DMG. This is where most of her damage comes from.
Other Traces. Module α (A2) adds +25% Break Effect in Complete Combustion and delays the countdown by 10% each time her Enhanced attacks break a Weakness (3 times max); Module γ (A6) gives +0.8% Break Effect per 10 ATK above 1,800.
Chrysalid Pyronexus (Talent). Up to 40% DMG reduction, always at maximum during Complete Combustion, plus +30% Effect RES.

Rotation

Use her Technique: at the start of each wave it implants Fire Weakness on all enemies and deals AoE damage.
Skill → Ultimate → spam her Enhanced Skill during Complete Combustion.
When the state ends, Skill once to refill Energy and go again. With The Dahlia's Energy refunds she can often re-enter it immediately.

Tips

She burns through Skill Points: The Dahlia, Gallagher or E1 (SP-free Enhanced Skill) solve that.
Her ATK matters because of her A6: outside ATK buffs indirectly raise her Break Effect.
Since 4.2, delaying the countdown can occasionally cost you a quick exit-and-re-enter cycle; for most players, simply staying in Complete Combustion longer is better.

Strengths

Excellent Super Break damage dealer
Constantly implants Fire Weakness on several enemies at once
Very high natural Toughness damage
Extremely durable, which allows sustain-less teams
Very fast, with built-in SPD boosts and action advances
Fully self-sufficient Energy economy

Weaknesses

Her premium team is a colossal upgrade over budget versions
Burns through Skill Points very quickly
The Dahlia is close to mandatory against today's Toughness bars
Needs very high stat investment to reach her peak

Notable dupes · Eidolon

Big upgrade

Her Enhanced Skill ignores 15% DEF and no longer costs Skill Points, which fixes her biggest weakness.

Big upgrade

Defeating or breaking an enemy with her Enhanced attacks grants an extra turn, now once per turn with no cooldown since 4.2.

Solid upgrade

+20% Fire RES PEN in Complete Combustion and another +50% Weakness Break Efficiency on her Enhanced attacks.

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Updated September 25, 2026 · Version 4.5

Sources & references