What is the best Light Cone for Ruan Mei?

Past Self in Mirror is the closest fit on the data: it is a 5-star Harmony Light Cone with 529 base ATK at level 80, and its passive acts on Break Effect. Memories of the Past is the best 4-star alternative.

Which relic set should Ruan Mei use?

Hunter of Glacial Forest. Its 2-piece bonus is: Increases Ice DMG by 10%. Its 4-piece bonus is: After the wearer uses their Ultimate, their CRIT DMG increases by 25% for 2 turn(s).

Which Planar Ornament should Ruan Mei use?

Forge of the Kalpagni Lantern. Its 2-piece bonus is: 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). Planar Ornaments have no 4-piece bonus; the sphere and the rope are the whole set.

Ruan Mei, Ice Harmony character | Honkai: Star Rail

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Ruan Mei Build

Build guide · Honkai: Star Rail

IceHarmonySupport

English voice: Emi Lo

The best Ruan Mei build in Honkai: Star Rail (Version 4.6) is Past Self in Mirror with Watchmaker, Master of Dream Machinations. Updated November 5, 2026

Abilities Traces Materials Eidolons

Where these rankings come fromThe light cone order, relic sets and stat priorities on this tab are prydwen.gg’s, measured in play and rephrased. Relative damage figures are ratios against the bottom of each ranking, not absolute numbers, and each one holds only for the superimposition and team its row states. Everything else (base stats, passive text, material totals) is read from the game’s own data.

Light cones

5 ranked

Past Self in Mirror, 5★ Harmony Light Cone | Honkai: Star Rail

BISPast Self in Mirror

Ranked first at S1

529

Base ATK · lv 80

1058 HP529 DEF

In Pursuit of the Wind, 4★ Harmony Light Cone | Honkai: Star Rail

#2In Pursuit of the Wind

Ranked #2 at S5

476

Base ATK · lv 80

1058 HP397 DEF

Memories of the Past, 4★ Harmony Light Cone | Honkai: Star Rail

#3Memories of the Past

Ranked #3 at S5

423

Base ATK · lv 80

953 HP397 DEF

Meshing Cogs, 3★ Harmony Light Cone | Honkai: Star Rail

#4Meshing Cogs

Ranked #4 at S5

318

Base ATK · lv 80

847 HP265 DEF

Dance! Dance! Dance!, 4★ Harmony Light Cone | Honkai: Star Rail

#5Dance! Dance! Dance!

Ranked #5 at S5

423

Base ATK · lv 80

953 HP397 DEF

Relics

3 sets

CoreWatchmaker, Master of Dream Machinations

Incredible team-wide supportive set for Break-focused teams. Most optimally played on the character in the team with the most frequent access to an Ultimate which buffs allies to ensure strong uptime. In teams with particularly fast Break-focused damage dealers, equipping this to multiple Supports for better uptime may be advised.

2PCIncreases Break Effect by 16%.

4PCWhen the wearer uses their Ultimate on an ally, all allies' Break Effect increases by 30% for 2 turn(s). This effect cannot be stacked.

Also works

Planar ornaments

Sphere and rope · 2-piece only

CoreSprightly Vonwacq

Incredibly strong option for buff/debuff based characters. The advance from this set allows the wearer to apply their buffs/debuffs before the rest of the team acts, accelerate rotations, allows access to ultimates closer to the start of the fight and also grants Energy Regen. A valuable stat for many supports.

2PCIncreases 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.

Also works

Main stats

Ultimate · 130 energy

Body: HP% > DEF%
Feet: Speed
Planar Sphere: HP% > DEF%
Link Rope: Energy Regen Rate > Break Effect

Substat priority

Highest first

1Break Effect (Until 180%)Best
2SPD (Until Breakpoint)
3HP% = DEF%
4Effect RES (30% if using Broken Keel)

Stack Break Effect until 180%. Aim for a desirable Speed breakpoint next (134 minimum recommended). After achieving these goals, stack more Break Effect to improve Ruan's burst damage or invest in more Speed or DEF% and HP% to make her more durable.

Trace priority

Level in this order

#1
Ultimate = Talent = Skill
Max first
#2
Basic
Then

Major traces, best first: Candle Lights on Still Waters (A6) > Inert Respiration (A2) > Days Wane, Thoughts Wax (A4)

Best Eidolons

E3 and E5 raise levels only

E1Neuronic Embroidery
E2Reedside Promenade
E3Level bump
E4Chatoyant Éclat
E5Level bump
E6Sash Cascade

E1
Neuronic Embroidery
Game text
While the Ultimate's Zone is deployed, the DMG dealt by all allies ignores 20% of the target's DEF.
E2
Reedside Promenade
Game text
While Ruan Mei is on the field, all allies increase their ATK by 40% when dealing DMG to enemies that are Weakness Broken.
E4
Chatoyant Éclat
Game text
When an enemy target's Weakness is Broken, Ruan Mei's Break Effect increases by 100% for 3 turn(s).
E6
Sash Cascade
Game text
Extends the duration of the Ultimate's Zone by 1 turn(s). The Talent's Break DMG multiplier additionally increases by 200%.

Teams

16 teams

Firefly team

Fire · BreakPlays Break amplifier

A Break Effect carry with two Harmony units that raise Break damage and Weakness Break efficiency, and a sustain that keeps Break uptime rather than adding damage.

FireflyMain DPS
Ruan Mei, this characterBreak amplifier
FugueWeakness implant
LingshaSustain · Break

Castorice team

Quantum · RemembrancePlays Harmony buffer

Castorice pays HP for her memosprite, so the line-up pairs a healer who profits from that with two Harmony units that raise the memosprite’s own damage.

CastoriceMain DPS
TribbieHarmony buffer
Ruan Mei, this characterHarmony buffer
HyacineSustain

Boothill team

Physical · BreakPlays Break amplifier

A single-target Break carry: one Harmony unit raises Break damage, one implants the Weakness he needs, and the sustain is the one that also breaks.

BoothillMain DPS
Ruan Mei, this characterBreak amplifier
FugueWeakness implant
GallagherSustain · Break

Rappa team

Imaginary · BreakPlays Break amplifier

Break damage across a whole wave rather than one target, so both Harmony slots go to Break amplification and the sustain adds Break of its own.

RappaMain DPS
Ruan Mei, this characterBreak amplifier
Trailblazer (Harmony)Break support
LingshaSustain · Break

Himeko • Nova team

Fire · EruditionPlays Harmony buffer

Her Talent hands every ally an Assist Skill that calls her Starblazer, so the other three slots are chosen for how often they take a turn.

Himeko • NovaMain DPS
SundayAction advance
Ruan Mei, this characterHarmony buffer
LingshaSustain

Argenti team

Physical · EruditionPlays Harmony buffer

His 180-energy Ultimate is the whole kit, so every other slot is chosen for how much Energy it returns rather than how much damage it adds.

ArgentiMain DPS
SundayAction advance
Ruan Mei, this characterHarmony buffer
HuohuoEnergy · Sustain

See all 16 on best teams

Honkai: Star Rail 5★ Ice Harmony Support

Ruan Mei build summary

Updated November 5, 2026

Past Self in Mirror tops the light cone ranking for Ruan Mei at S1, ahead of In Pursuit of the Wind, Memories of the Past and Meshing Cogs. That order is prydwen.gg's, measured in play and rephrased here; every row of it sits under Light cones below.

Run Watchmaker, Master of Dream Machinations on Ruan Mei, with Messenger Traversing Hackerspace and Thief of Shooting Meteor behind it. The planar ornament is Sprightly Vonwacq. Main stats are HP% > DEF% body, Speed feet, HP% > DEF% sphere, Energy Regen Rate > Break Effect rope. Roll substats in the order Break Effect (Until 180%) > SPD (Until Breakpoint) > HP% = DEF% > Effect RES (30% if using Broken Keel).

Trace priority is Ultimate = Talent = Skill > Basic. The Ultimate costs 130 energy, which is what an Energy Regeneration Rate target has to clear.

Ruan Mei plays Break amplifier in the Firefly team, alongside Firefly, Fugue and Lingsha.

Role: Support
Best light cone: Past Self in Mirror
Alternatives: In Pursuit of the Wind, Memories of the Past, Meshing Cogs
Relic set: Watchmaker, Master of Dream Machinations
Planar ornament: Sprightly Vonwacq
Main stats: HP% > DEF% body, Speed feet, HP% > DEF% sphere, Energy Regen Rate > Break Effect rope
Substat priority: Break Effect (Until 180%) > SPD (Until Breakpoint) > HP% = DEF% > Effect RES (30% if using Broken Keel)
Trace priority: Ultimate = Talent = Skill > Basic
Best team: Firefly, Ruan Mei, Fugue, Lingsha
Ultimate energy cost: 130 energy
Key ascension material: 65× Gelid Chitin
Last updated: November 5, 2026

Ruan Mei build FAQ

What is the best Light Cone for Ruan Mei?: Past Self in Mirror is the closest fit on the data: it is a 5-star Harmony Light Cone with 529 base ATK at level 80, and its passive acts on Break Effect. Memories of the Past is the best 4-star alternative.
Which relic set should Ruan Mei use?: Hunter of Glacial Forest. Its 2-piece bonus is: Increases Ice DMG by 10%. Its 4-piece bonus is: After the wearer uses their Ultimate, their CRIT DMG increases by 25% for 2 turn(s).
Which Planar Ornament should Ruan Mei use?: Forge of the Kalpagni Lantern. Its 2-piece bonus is: 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). Planar Ornaments have no 4-piece bonus; the sphere and the rope are the whole set.

Ruan Mei Build

Light cones

Relics

Planar ornaments

Main stats

Substat priority

Trace priority

Best Eidolons

Neuronic Embroidery

Reedside Promenade

Chatoyant Éclat

Sash Cascade

Teams

Ruan Mei build FAQ