Guide
How the kit works
Start with Ice Fog Piercer. Its initial stab deals Cryo DMG and creates the Frostpierce Star. Normally, the Star periodically fires crystals at nearby enemies. Each crystal that hits gives the Traveler one Frostglow stack, up to eight. Outside combat, Frostglow expires after 30 seconds.
Inside a Polestar Field, Stellar Jubilee: Illusory Frostmirror puts the Traveler in Radiance: Stellar-Conduct. In that state, the Star fires coordinated crystals when the Traveler hits with a Normal, Charged or Plunging Attack, rather than firing periodically. A coordinated attack can trigger once every 0.2 seconds. Ever-Keen Frost also converts those attacks to Cryo DMG while the Star is present and increases their damage by 80% of the Traveler's ATK.
Use Frostbound Javelin after building Frostglow. It consumes every stack to increase its damage, and consuming eight adds more javelin damage instances. In Radiance: Stellar Glimmer, the Burst damage changes to Cryo DMG of the corresponding Stellar Glimmer reaction type.
Foreign Permafrost grants Icepoint when a nearby party member deals Stellar-Conduct or Stellar Swirl DMG. At three stacks, a Charged Attack becomes Freezing Ice, consuming them and granting two Frostglow. Freezing Ice can occur once every 15 seconds and does not receive the damage increase from Ever-Keen Frost.
Build and why
For team support, try four pieces of Tenacity of the Millelith. An Elemental Skill hit increases nearby party members' ATK by 20% and Shield Strength by 30% for three seconds, even if the wearer is off-field. The set does not create a shield.
For the Traveler's damage in Stellar-Conduct teams, use four pieces of Disenchantment in Deep Shadow. It gives ATK, increases Stellar-Conduct reaction damage by 40%, and gives attacks 16% CRIT Rate against opponents affected by Superconduct or Stellar-Conduct. Heart of the Furnace is another four-piece option: it gives the wearer ATK after a Stellar Glimmer trigger or damage and raises nearby party members' Stellar Glimmer reaction damage by 50%.
For Stellar Swirl, Scarlet Proof is worth considering. Its four-piece effect gives CRIT Rate and Stellar Swirl reaction damage after the wearer triggers Stellar Swirl. Use ATK Percentage on the sands and goblet, with CRIT DMG or CRIT Rate on the circlet. The game's substat order is CRIT DMG, CRIT Rate, ATK Percentage, then Elemental Mastery. ATK also feeds the Traveler's Lucent Ice passive, which grants Elemental Mastery based on ATK.
Exaiphanes Blade is the first weapon choice: after the Traveler hits an opponent, it grants ATK and restores Energy, including off-field. Primordial Jade Cutter supplies ATK based on Max HP. Wolf-Fang increases Skill and Burst damage, with separate CRIT Rate stacks for each.
Leveling priority
I'd level Frostbound Javelin first because it deals multiple hits and rewards a full set of Frostglow stacks. Ice Fog Piercer is next: its initial hit and crystals deal Cryo DMG throughout the rotation. Leave Foreign Frostglint (NA) until later, particularly if the Traveler spends much of the fight off-field. If you use their weapon attacks often in Radiance: Stellar-Conduct, keep those levels in mind too.
Ascension uses Mora, Windwheel Aster, Brilliant Diamond Sliver, Brilliant Diamond Fragment, Brilliant Diamond Chunk and Brilliant Diamond Gemstone. You also need Damaged Mask, Stained Mask and Ominous Mask.
Skill upgrades use Mora and Crown of Insight, along with Teachings of Charity, Guide to Charity and Philosophies of Charity. They also need Guide to Fortitude, Philosophies of Fortitude, Guide to Glory and Philosophies of Glory, plus Chimeric Core, Symbiotic Chimeric Nucleus, Prime Chimeric Nexus and Ascended Sample: Queen.
Constellations worth it
Brumal Grimfrost is the standout upgrade for a Stellar Glimmer team. Each Frostglow stack consumed by the Burst increases other party members' Stellar Glimmer reaction damage by 5% for 15 seconds, up to 40%. The bonus is for the other party members, so don't count it as a direct buff to the Traveler.
Frostfall Reverberation is worth considering for the active character: a crystal hit grants 60 Elemental Mastery for five seconds. That boost becomes 120 for its duration if the affected character triggers a Stellar Glimmer reaction or deals its reaction damage. Enduring Ice is another useful option, extending the Star's duration by 25%.
Glacial Shard and Bittercold Fog add three levels to the Burst and Skill respectively. If you are choosing where to stop, you can pass on making those level increases a goal by themselves. Somber Freeze gives the Traveler five Elemental Energy when they deal Stellar Glimmer DMG, at most once every 0.5 seconds.
Teams
The Star can follow whichever party member is active, while its crystals build the Traveler's Frostglow. In Radiance: Stellar-Conduct, remember that coordinated crystals require the Traveler's own weapon attacks, not those of the active teammate.
Common mistakes
Don't spend Frostbound Javelin immediately every time without checking Frostglow. Eight stacks give it extra damage instances, though there can be situations where using the Burst earlier fits your rotation.
Don't assume Ice Fog Piercer fires periodically in every state. During Radiance: Stellar-Conduct, use the Traveler's own weapon attacks to trigger coordinated crystals. Watch for three Icepoint stacks too, but remember that Freezing Ice has its own 15-second limit.
Don't build only Elemental Mastery and overlook ATK or CRIT stats. ATK feeds several parts of the kit, while the recommended artifact stats favor CRIT and ATK Percentage. If you use Tenacity of the Millelith for team buffs, bring a separate shield source if you want to benefit from its Shield Strength bonus.
