Image Credit: HoyoVerse

Firefly has returned in Honkai Star Rail with her Break DPS role firmly established as one of the strongest ways to control enemies and deal massive Super Break Damage. She thrives in teams built around Weakness Breaks, Break Effect stacking, and fast Speed rolls so she can act often and hit hard when enemies enter their weakest state.

This guide gives you specific weapons (Light Cones), best relic sets, stat priorities, and team recommendations for building her to dominate battles.

Firefly’s Role and What She Does

Firefly is a 5-star Destruction Path Break Damage Dealer (SAM) who excels in lowering enemy Toughness and maintaining high Break Effect so she can score huge Super Break Damage when an enemy’s Weakness Bar is depleted. Her kit encourages frequent action, Break stacking, and exploiting Fire weaknesses on enemies to maximize her damage uptime.

Her Ultimate puts her into a state called Complete Combustion, during which her speed, break effect, and Break damage output increase, making her especially lethal in long fights.

Light Cones (Weapons) for Firefly

Your Light Cone choice is one of the most impactful parts of her build. These options maximize Break Effect or overall damage potential:

Best Light Cone

Whereabouts Should Dreams Rest
This is her best-in-slot Light Cone. It increases her Break Effect by a huge amount and also applies Routed to enemies when she deals Break Damage, which lowers their Speed and amplifies the Break Damage they take. This synergizes perfectly with her core mechanics.

Great Alternatives

• On the Fall of an Aeon
  Provides bonus ATK and increases overall damage. It synergizes well with Firefly’s tendency to deal repeated Break Damage.
• Indelible Promise (4-star)
  A good Free-to-Play Light Cone that boosts Break Effect stacks.
• Something Irreplaceable or Nowhere to Run
  These also work as substitutes, offering high base Attack and supportive stats until you get better options.

Note: Firefly’s kit does not scale with CRIT stats, so Light Cones that give break effect or ATK are far better than those focused on crit.

Best Relics for Firefly

Relics are how you unlock Firefly’s true potential in long fights and high-end content.

Best in Slot Relic Set

Iron Cavalry Against the Scourge (4-Piece)

• 2-Piece: +16% Break Effect
• 4-Piece: If Firefly’s Break Effect is over 150%, her Break Damage ignores 10% of enemy DEF. If her Break Effect is over 250%, her Super Break Damage ignores 15% of enemy DEF as well.
  This set is tailor-made for Firefly, boosting both her damage output and the value she gets from high Break Effect values.

Good Alternative

Thief of Shooting Meteor (4-Piece)

• 2-Piece: +16% Break Effect
• 4-Piece: +16% Break Effect plus energy regeneration when Weakness Breaks are inflicted
  This is easier to farm and helps Firefly build energy as she Breaks enemies.

Planar Ornament Sets

Planar Ornaments give bonus stats outside the normal relic system. These are the best options for Firefly:

Best Ornament Set

Forge of the Kalpagni Lantern (2-Piece)

• +6% Speed
• When hitting enemies with Fire Weakness, +40% Break Effect for one turn
  This is perfect for Firefly since she frequently applies Fire Weakness, giving essentially constant Break Effect boosts.

Alternative Ornament Set
Talia: Kingdom of Banditry (2-Piece)

• +16% Break Effect
• Extra +20% Break Effect once Firefly reaches high SPD (145+), a breakpoint she should easily hit with her kit and relics.

Stat Priorities

Knowing what stats to chase on relics and ornaments will make or break your Firefly build.

Main Stat Priorities

• Body Relic: ATK%
• Feet Relic: Speed
• Planar Sphere: ATK%
• Link Rope: Break Effect%
  This ensures she gets strong Break scaling while acting often via high Speed.

Substat Priority

1. Break Effect%
2. Speed
3. ATK%
4. Additional ATK
   Firefly does not rely on crit, so you can safely ignore crit rate and crit damage stats.

Recommended Benchmarks

Stack enough Speed to reach around 150 SPD in the character sheet, which turns into around 210 SPD in combat after her Ultimate bonus for extra actions. Aim for very high Break Effect (250% or more) to unlock her Relic set’s full DEF ignore.

Trace and Talent Priorities

To make Firefly as potent as possible:

• Ultimate Trace: Highest priority (because it unlocks her Complete Combustion state and major damage buffs)
• Skill and Talent Traces: Next in importance since the Skill generates energy and Talent improves survivability and resistance
• Basic Attack Trace: Lowest priority since Firefly rarely uses normal attacks in high-level play

Best Teams for Firefly

Firefly works best with characters who buff her Break Effect, increase Break Damage, or provide supportive buffs that extend her uptime.

Premium Break Damage Team

• Firefly (Main Break DPS)
• The Dahlia (Support) – Provides a massive Break Effect and boosts Super Break Damage output
• Ruan Mei (Support) – Increases allies’ damage, Break Effect, and RES penetration
• Harmony Trailblazer or Fugue (Support / Buff) – Gives Break Effect buffs and ensures Firefly gets an extra instance of Super Break Damage per rotation.

This core team dramatically amplifies Firefly’s damage output and ensures her Break rotations apply frequently.

Free-to-Play Friendly Team

• Firefly
• Harmony Trailblazer (Imaginary) – Buffs Break Effect and extends Weakness Break duration
• Asta – Speed buffs help her act faster
• Lynx – Provides healing and utility while letting Firefly stay alive longer

This team performs well without heavy investment in premium characters.

Final Tips for Mastering Firefly

Firefly is strongest when she can act often and apply Break Effect consistently. Prioritize building Speed and Break Effect early and make sure her Relic sets and Light Cones synergize with her Break-focused damage mechanics. With high Break Effect and the right support, her Super Break Damage can delete enemy targets before they can act again.

Pro Tip: Because Firefly does not need crit stats, you can focus entirely on Break Effect, Speed, and ATK. Her damage will scale more reliably than most crit-based DPS units.

If you want more up-to-date Honkai Star Rail build guides, advanced team templates, and stats benchmarks to help you optimize every character, subscribe to The Gamers Cut. We deliver clear, actionable guidance backed by community and data-driven insight so your roster stays powerful every patch.