Guide
How the kit works
Start with White Clouds at Dawn. Xianyun enters Cloud Transmogrification and performs one Skyladder leap. You can use Skyladder up to two more times, including in mid-air, then plunge to release Driftcloud Wave. Each leap increases that wave’s damage and area. The wave counts as Plunging Attack DMG and ends the state.
Land the wave on opponents to activate Galefeather Pursuit. Each opponent hit grants one Storm Pinion stack for 20 seconds, up to four. The stacks give party members 4%, 6%, 8% or 10% Plunging Attack CRIT Rate. Each stack has its own duration.
Use Stars Gather at Dusk to deal AoE Anemo DMG, heal nearby characters and summon Starwicker. It follows the active character, periodically heals the party and starts with eight Adeptal Assistance stacks. While stacks remain, the active character jumps higher; completing a plunge consumes one stack and makes Starwicker deal AoE Anemo DMG.
Consider, the Adeptus in Her Realm adds 200% of Xianyun’s ATK to the active character’s plunge shockwave damage while Adeptal Assistance remains, up to 9,000. Each shockwave applies the increase to only one opponent, and each character can trigger it once every 0.4 seconds. Word of Wind and Flower (NA) covers Xianyun’s regular Anemo attacks, but a support build spends less time using them.
Build and why
Use four pieces of Viridescent Venerer. Its Swirl reaction damage bonus is 60%, and triggering Swirl lowers the opponent’s RES to the infused element by 40% for 10 seconds. Apply an element to the target before Xianyun attacks if you want her to trigger the reaction.
Four pieces of Song of Days Past are another option: healing recorded over six seconds becomes a damage increase equal to 8% of the recorded amount, for up to five hits or 10 seconds. Four pieces of Noblesse Oblige instead give the party 20% ATK for 12 seconds after a Burst; that effect cannot stack.
Choose ATK Percentage or Energy Recharge on the sands, ATK Percentage on the goblet, and ATK Percentage or Healing Bonus on the circlet. For substats, look for Energy Recharge first, followed by ATK Percentage, CRIT Rate and ATK. ATK supports both healing and the plunge shockwave bonus; Energy Recharge helps keep the Burst available.
Crane's Echoing Call is the first weapon choice. After Xianyun hits an opponent with a plunge, it increases nearby party members’ Plunging Attack DMG by 28% for 20 seconds. Their plunge hits can also restore Energy to her. Favonius Codex is next: its CRIT hits can generate particles, so CRIT Rate matters. Skyward Atlas is another option for its Elemental DMG Bonus. Oathsworn Eye is worth considering for the Energy Recharge gained after using a Skill.
Leveling priority
For a support build, I suggest leveling Stars Gather at Dusk first because it provides the party’s healing and Starwicker. Raise White Clouds at Dawn next for Xianyun’s own damage. Leave Word of Wind and Flower (NA) until later if she rarely attacks on field. Her plunge shockwave bonus comes from a passive, not from leveling her Normal Attack.
For ascension, gather Mora, Clearwater Jade, Vayuda Turquoise Sliver, Vayuda Turquoise Fragment, Vayuda Turquoise Chunk, Vayuda Turquoise Gemstone and Cloudseam Scale. You also need Divining Scroll, Sealed Scroll and Forbidden Curse Scroll.
Talents use Mora and those three scrolls as well, plus Teachings of Gold, Guide to Gold, Philosophies of Gold and Lightless Eye of the Maelstrom. Crown of Insight is needed for the final talent levels.
Constellations worth it
Aloof From the World is the biggest support upgrade. After a Skyladder, Xianyun gains 20% ATK for 15 seconds. It also changes the passive plunge shockwave increase from 200% to 400% of her ATK and raises its cap from 9,000 to 18,000.
Purifying Wind is a useful step before it: an extra Skill charge gives you more flexibility with Xianyun’s leaps. For an on-field approach, consider They Call Her Cloud Retainer. It increases Driftcloud Wave CRIT DMG according to the number of Skyladders used, and for 16 seconds after her Burst the Skill does not enter cooldown, until it has been used eight times.
You can stop at C2 if you want her support effects rather than the later upgrades. Creations of Star and Moon raises Burst level, Mystery Millet Gourmet adds healing when Driftcloud Wave hits, and Astride Rose-Colored Clouds raises Skill level. Consider those as steps toward C6 rather than necessities.
Teams
Put Xianyun beside an active character you want to use Plunging Attacks with. Xiao is an Anemo option, while Gaming and Diluc are Pyro choices; Varesa gives you an Electro option. Xianyun supplies the jump height, healing and plunge bonuses for that style of play.
Furina is a Hydro teammate who can contribute while off field. Bennett and Xiangling are Pyro options, and Faruzan is an Anemo option alongside Xiao. Pick the remaining slots around the damage you want the team to deal. With Viridescent Venerer, Xianyun can trigger Swirl and lower resistance to the element involved.
Common mistakes
Do not let Cloud Transmogrification expire before plunging if you want Driftcloud Wave and its Storm Pinion stacks. If you choose not to use the wave, the next cooldown of White Clouds at Dawn is reduced by three seconds.
Do not expect the plunge shockwave bonus to hit every enemy in a group. Each shockwave applies it to one opponent, and it needs Starwicker to have Adeptal Assistance remaining.
Do not build only for ATK if that leaves Stars Gather at Dusk unavailable when you need healing and jumps. Energy Recharge matters too. With Crane's Echoing Call, remember to hit an opponent with Xianyun’s own plunge to start its team damage bonus.
