Iansan

4★

ElectroPolearmSupport

TL;DR

Iansan's Burst drops a scale that follows your active character and hands them a large Attack bonus for 12 seconds. The bonus is at its best while her Nightsoul meter stays topped up. The scale refills that meter based on how far your active character moves. Skill, one attack, Burst, swap off and keep moving.

Rotation

Skill (E) to charge forward. Her Nightsoul meter fills and the ring appears around her portrait.
One Normal Attack straight after. It comes out as her stomp without costing stamina and turns on her own 20% Attack for 15 seconds.
Burst (Q) to put the scale down.
Swap to your damage dealer and keep them moving for the next 12 seconds. Distance covered is what refills her meter.

Abilities

Skill (E)	A charge forward for Electro damage. Fills her Nightsoul meter and starts her Nightsoul state. 16 second cooldown. For 5 seconds afterwards, a Normal Attack gets you one stomp without paying stamina for it.
The stomp	What her Charged Attack becomes while the Nightsoul state is up: area Electro damage for a chunk of stamina, or free in the window after the Skill. Landing it gives her 20% Attack for 15 seconds.
Burst (Q)	70 Energy, 18 second cooldown. Area Electro damage, a top-up to her meter, then the scale for 12 seconds. The scale buffs your active character's Attack and refills her meter from their movement.
Her Nightsoul meter	Drains the whole time the state is running. At 42 points or above the Attack bonus is the strong version, which scales off her Attack. Below that it drops to a weaker one.

The one mechanic to understand

The buff is paid for by moving.

The scale keeps a running tally of how far your active character travelled in the last second and gives Iansan Nightsoul points back for it. Her meter drains constantly, so a carry who stands rooted to one spot lets it slip under the line and the bonus drops to its weaker form part way through the 12 seconds. Anyone who dashes, plunges or repositions between attacks keeps it topped up without thinking about it. The other half of this is the order of the buttons: her Nightsoul state normally ends the moment she leaves the field. The one thing that keeps it alive off the field is the scale. Swap away without casting the Burst and the meter empties behind you.

What actually matters

Energy Recharge, a great deal of it. 70 Energy every rotation off a character who generates very few particles herself. Roughly 240% on her own, a long way under that with Favonius Lance and a second Electro character.
Her Attack. The stronger version of the bonus scales off her Attack and nothing else, so levelling her and stacking Attack is what makes your carry hit harder.
The Burst goes last. Skill, attack, Burst, swap. Any other order and she loses her meter on the way out.

Gear

Weapon	Energy Recharge first, Attack second. Favonius Lance is the pick because its passive coughs up the particles she doesn't make for herself. It sits on the standard banner, so plenty of people already have one.
Artifacts	4-piece Scroll of the Hero of Cinder City, which turns her Electro reaction into a party-wide elemental damage bonus while she's in her Nightsoul state. Take 4-piece Noblesse Oblige if her Electro has nothing to react with, since 20% party Attack asks for no conditions at all.

Sands	Goblet	Circlet	Substats
ATK / ER	ATK	ATK / Crit Rate	ATK / ER

Take a Crit Rate circlet if you're running Favonius Lance and want its passive going off reliably. Energy Recharge sands while you're short of the number above.

Works well with

Dendro

Hydro

The Attack bonus is element-blind, so it works for any carry who wants Attack. The elements above are just the reactions her Electro sets up on the way past. What she really asks for is a carry who moves.

Don't bother

Her own damage. Three spear pokes and a dash, none of it worth a Crit substat.
Her healing. It only exists when a Natlan character sets off a Nightsoul burst nearby, herself included. Even then it won't keep anyone alive on its own.
Counting her points. Keep the carry moving and the meter looks after itself.
The Nightsoul sprint. Very good for crossing Natlan, does nothing in a fight.

Want the full deep dive? Read Iansan on KeqingMains.

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