Beidou

4★

ElectroClaymoreOff-field Damage

TL;DR

Everything Beidou does for a team comes from her Burst. Cast it and your active character's Normal Attacks throw off a bolt of lightning about once a second for the next 15 seconds. They take less damage while it runs too. Once her Witch's Revelation quest is done, holding the Skill charges it on its own and the release refunds 16 of the Burst's 80 Energy. Hold Skill, release it into an enemy, Burst, then swap to whoever spends the fight swinging.

Rotation

Hold Skill (E) for a couple of seconds and release it into an enemy. With her Witch's Revelation quest done the charge builds on its own, the hit refunds 16 Energy and the Skill is ready again straight away.
Tap Skill (E) again for a second lot of particles.
Burst (Q). Lightning wraps around whoever is on the field.
Swap to your Normal Attack damage dealer for the 15 seconds it runs.
Come back for the next Burst in 20 seconds.

Abilities

Skill (E)	7.5 second cooldown. Tap for a forward Electro swing. Hold to raise the claymore as a shield that soaks damage based on her Max HP, then release for a hit that grows with the charge she built while holding. Two charges is the cap. As pulled she only charges when something hits her. After her Witch's Revelation quest a charge also builds on its own every 0.8 seconds. Releasing a charged hold into an enemy then takes 4 seconds off the cooldown and refunds 8 Energy per charge, once every 15 seconds.
Burst (Q)	80 Energy, back in 20 seconds. Runs 15 seconds. Your active character's Normal and Charged Attack hits set off a lightning discharge that jumps between enemies, at most once a second. They also take less damage and get harder to knock about.

Skill (E)

7.5 second cooldown. Tap for a forward Electro swing. Hold to raise the claymore as a shield that soaks damage based on her Max HP, then release for a hit that grows with the charge she built while holding. Two charges is the cap. As pulled she only charges when something hits her. After her Witch's Revelation quest a charge also builds on its own every 0.8 seconds. Releasing a charged hold into an enemy then takes 4 seconds off the cooldown and refunds 8 Energy per charge, once every 15 seconds.

Burst (Q)

80 Energy, back in 20 seconds. Runs 15 seconds. Your active character's Normal and Charged Attack hits set off a lightning discharge that jumps between enemies, at most once a second. They also take less damage and get harder to knock about.

The one mechanic to understand

The Burst attacks with your carry, not with her.

Everything worth having is spent on somebody else's turn on the field. The discharge fires off the active character's Normal and Charged Attacks, so it wants a character who stands there hitting things rather than one who casts and leaves. The once a second cap means a very fast attacker gets no more out of it than a steady one.

What actually matters

Energy Recharge. 80 Energy on the Burst that is the entire reason she's in the party. Around 200% if she's your only Electro character, less with a second one. A charged hold of the Skill refunds 16 Energy and resets the cooldown, so hold it, then tap it again for more particles.
Do the Witch's Revelation quest. Get her to level 70 and play it. Without it the hold only charges when something hits her and refunds nothing.
The lightning scales off her stats. Attack, Crit and Electro damage on Beidou all show up in numbers your carry appears to be dealing, so she still needs building even though the hits happen while she's away.
She needs a Normal Attack carry. A character who presses two buttons and swaps out leaves most of the Burst unspent.

Gear

Weapon	Energy Recharge first. Favonius Greatsword carries it and drops extra particles when she crits.
Artifacts	4-piece Emblem of Severed Fate. Energy Recharge on the 2-piece, then Burst damage scaled off however much of it she ends up with.

Sands	Goblet	Circlet	Substats
ER	Electro DMG	Crit	Crit / ATK

Works well with

Hydro

Cryo

Hydro for Electro-Charged, since the discharge jumps between wet enemies anyway. Cryo if your carry is dealing Physical damage.

Don't bother

Timing the hold as a parry. After her quest the charge builds on its own in under two seconds, so she doesn't need to be hit.
Physical builds. The Burst is Electro from end to end.
Her own attack strings. She casts and leaves.
Chasing the exact Energy Recharge number. Get the Burst out every rotation and stop reading.

Want the full deep dive? Read Beidou on KeqingMains.

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