The Dahlia is an excellent character designed specifically for Break teams. Her core kit focuses on applying multiple debuffs to enemies while significantly amplifying her allies’ Toughness Break effectiveness. She is clearly tailored to excel in Firefly’s Super Break team, but her versatility allows her to function well alongside other Break-oriented DPS characters such as Rappa, Boothill, Himeko, and Xueyi.
Best Cavern Relics
(2) Increases Break Effect by 16%.
(4) If 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.
This is currently her best-in-slot set for fully maximizing Dahlia’s potential. She only needs at least 250% Break Effect to consistently trigger the debuffs granted by the set’s 4-piece effect.
(2) Increases Break Effect by 16%.
(4) Increases the wearer's Break Effect by 16%. After the wearer inflicts Weakness Break on an enemy, regenerates 3 Energy.
This set is a solid alternative; however, it is more focused on energy regeneration, allowing for faster Ultimate activation.
Best Planar Ornaments
(2) Increases 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).
This is her best-in-slot set, but it requires Firefly to unlock its full effect.
(2) Increases the wearer's Energy Regeneration Rate by 5%. When the wearer's SPD reaches 120 or higher, the wearer's action is Advanced Forward by 40% immediately upon entering battle.
This is particularly effective for improving team turn order at the start of battle, while also providing a small amount of Energy Regeneration.
(2) Increases 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%.
Talia is also a strong option, though it provides a lower Break Effect bonus.
Best Stats

Body
HP% / DEF%

Boots
SPD

Sphere
HP% / DEF%

Rope
Break Effect / Energy Regeneration Rate
Substats
Break Effect / SPD / HP% / DEF%
info
The only stat Dahlia must reach is 250% Break Effect in order to activate the debuff from the 4-piece Iron Cavalry set. Beyond that requirement, her main stats and substats should focus on survivability and Speed, allowing her to take turns more frequently.
Best Light Cones
SourceLight Cone Event Warp
Immolation
Increases the wearer's Break Effect by 60~120%. When entering combat, increases Break DMG dealt by the wearer and another teammate who triggered combat by 32~72%. If there is no teammate who triggered combat, applies this effect to the wearer and the teammate with the highest Break Effect. Effects of the same type cannot be stacked. When the wearer applies Weakness to an enemy target, recovers 1 Skill Point. This effect can only trigger once, and trigger count resets when using Ultimate.This is her best Light Cone.
SourceLight Cone Event Warp
Rebirth
Increases the wearer's Break Effect by 60~100%. When an enemy target's Weakness gets broken, there is a 100% base chance to inflict the "Charring" state on it, which increases its Break DMG taken by 18~30%, lasting for 2 turn(s). This effect can stack 2 time(s).SourceStellar Warp, Departure Warp, Character Event Warp, Light Cone Event Warp
Glance Back
When the wearer hits an enemy and if the hit enemy is not already "Ensnared," then there is a 60~100% base chance to "Ensnare" the hit enemy. "Ensnared" enemies' DEF decreases by 12~16% for 1 turn(s).This is her best 4★ Light Cone, applying DEF Shred to a single enemy—making it especially effective against boss encounters.