Honkai: Star Rail Firefly Build Guide: Best Light Cones, Relics, Team Comps & Playstyle

Firefly, the 5-star Fire Destruction character in Honkai: Star Rail, specializes in Break Effect and Super Break Damage through her high-frequency skill rotations and self-advancing mechanics. As a hyper-specialized Break DPS, she dominates against enemies with Fire weakness and excels in fast-paced combat. This guide covers optimal builds, team synergies, and strategies to maximize her potential.  

1. Skill Priority & Talent Breakdown  

- Ultimate (Q) > Skill (E) > Talent > Basic Attack   

  - Ultimate (Q): Firefly’s core ability, entering "Complete Combustion" mode to boost Speed by 60 and Break Efficiency by 50%. Prioritize maxing this first.  

  - Skill (E): Restores 60% Energy and self-advances action by 25%, critical for maintaining Ultimate uptime. Level second.  

  - Talent: Provides up to 40% DMG reduction and 30% Effect RES during Ultimate. Upgrade for survivability.  

  - Basic Attack: Low priority; only used for Skill Point generation in emergencies.  

Key Mechanics  

- Break Efficiency: Firefly’s Ultimate and Skill grant massive Break DMG multipliers, especially with allies like Ruan Mei.  

- Self-Advance: Skill’s 25% action advance reduces downtime between Ultimates.  

- Weakness Implant: Enhanced Skill adds Fire weakness to enemies, enabling Break against non-Fire foes.  

2. Light Cone Recommendations  

Best-in-Slot  

- Where Dreams Return (5★): Signature Light Cone, boosting Break Effect by 48% and applying DEF shred on Break. Perfect for maximizing Super Break DMG.  

- On the Fall of an Aeon (5★): Free-to-play option from Herta’s Store. Provides 64% ATK and Break DMG buffs at S5.  

Alternatives  

- Something Irreplaceable (5★): Boosts ATK and restores HP, enhancing survivability.  

- Moles Welcome You (4★): Grants Break Effect and Energy Regeneration for faster rotations.  

3. Relic Sets & Stats  

Optimal Relic Combos  

- 4pc Iron Cavalry Against Scourge + 2pc Talia, Kingdom of Banditry  

  - 4pc Iron Cavalry: Increases Break Effect by 16% and boosts DMG by 12% after Ultimate.  

  - 2pc Talia: Adds 16% Break Effect, synergizing with Firefly’s kit.  

Transitional Sets  

- 4pc Thief of Shooting Meteor + 2pc Talia: Budget option for early-game Break DMG focus.  

Main Stats  

- Body: ATK% (converts to Break Effect via Trace)  

- Feet: SPD (aim for 150+ pre-Ultimate to achieve 210+ during Ultimate).  

- Planar Sphere: Fire DMG%  

- Link Rope: Break Effect (priority) or Energy Regeneration.  

- Substats: Break Effect > SPD > ATK% > Effect RES.  

4. Team Compositions  

Firefly thrives in teams that amplify Break DMG and sustain Skill Points:  

Meta Break Team  

- Firefly + Ruan Mei + Harmony Trailblazer + Gallagher/Lingsha  

  - Ruan Mei: Boosts Break Efficiency and extends Weakness Break duration.  

  - Harmony Trailblazer: Applies Fire weakness and buffs Break DMG via "Accompaniment".  

  - Gallagher/Lingsha: Provides healing, debuff cleanse, and additional Break support.  

F2P-Friendly Team  

- Firefly + Asta + Herta + Gallagher  

  - Asta: Buffs Fire DMG and SPD.  

  - Herta: Sub-DPS for extra Break DMG in multi-wave fights.  

5. Eidolon (Constellation) Highlights  

- E1: Reduces Skill Point consumption during Ultimate, easing rotations.  

- E2: Grants an extra action after defeating enemies, enhancing multi-wave performance.  

- E6: Increases Break DMG by 50% and ignores 25% enemy DEF during Ultimate. Game-changing for endgame.  

6. Playstyle & Rotation Tips  

1. Pre-Ultimate Setup: Use Skill → Basic Attack to generate Energy.  

2. Ultimate Burst: Activate Ultimate → Spam Enhanced Skill (4x) for Break DMG.  

3. Weakness Management: Prioritize enemies without Fire weakness using Enhanced Skill’s implant.  

4. Energy Management: Pair with Harmony Trailblazer or Energy Regeneration rope for 2-turn Ultimate cycles.  

7. Ascension & Trace Materials  

Ascension (Lv. 80)  

- Extinguished Core ×15  

- Suppressing Edict ×28 (Stagnant Shadow: Shape of Celestial)  

- Lumidouce Bell ×168 (Penacony local specialty).  

Trace Upgrades  

- Tracks of Destiny ×8  

- Key of Inspiration ×12  

- Credit Cost: ~3,000,000.