Guide
How the kit works
Use Tidecaller when you have an opening or expect a hit. Pressing it deals Electro damage immediately. Holding it raises a shield and releases an Electro strike when you let go or the skill expires. The shield's maximum absorption scales with Beidou's Max HP and has 250% Electro DMG Absorption Efficiency.
The held strike gains damage when Beidou is attacked, reaching its greatest damage bonus after two hits. You can also get that maximum bonus by countering at the precise moment she is hit. After a maximum-bonus Tidecaller, her Normal and Charged Attacks gain 15% damage and 15% attack speed for 10 seconds, and Charged Attacks have a much shorter delay.
Holding the skill also builds one stack of power every 0.8 seconds, even without an incoming attack. If the released strike hits, each stack reduces the skill cooldown by 4 seconds and restores 8 Energy to Beidou. This effect can trigger once every 15 seconds.
Use Stormbreaker for its Electro damage and protective effect, then land Normal or Charged Attacks to trigger its lightning. A discharge can occur at most once per second. Oceanborne (NA) has up to five Normal Attack strikes; its Charged Attack consumes Stamina for continuous slashes, followed by a stronger final slash.
Build and why
Four pieces of Emblem of Severed Fate are the main recommendation. Two pieces give 20% Energy Recharge, while four increase Elemental Burst damage by 25% of Energy Recharge, up to a 75% damage bonus. Both effects fit a build centered on Stormbreaker.
Four pieces of Noblesse Oblige are a team-focused option: two give 20% Elemental Burst damage, and the full set gives the party 20% ATK for 12 seconds after a Burst. That party bonus does not stack. You can also combine its two-piece bonus with two pieces of Thundering Fury for 15% Electro DMG Bonus.
Four pieces of Thundersoother are another option if opponents are affected by Electro: the set increases damage against them by 35%. Its bonus depends on that condition, unlike the Burst bonus from Emblem of Severed Fate.
Use Energy Recharge or ATK Percentage on the sands, Electro DMG Bonus on the goblet, and CRIT Rate or CRIT DMG on the circlet. For substats, look for Energy Recharge first, followed by CRIT Rate, CRIT DMG and ATK Percentage. Balance the circlet with the CRIT stats you already have.
Serpent Spine is the first weapon pick. It builds damage while Beidou is on the field, but also makes her take more damage and loses a stack when she takes damage. A Thousand Blazing Suns gives CRIT DMG and ATK after a Skill or Burst. Wolf's Gravestone gives ATK and can also raise the party's ATK when hitting an opponent below 30% HP.
The Unforged is another option, particularly with a shield: it increases Shield Strength and gains extra ATK from hits, with that ATK increase doubled while protected by a shield. Guides differ on their first weapon pick, so consider which conditions you can use.
Leveling priority
A good leveling order for this build is Stormbreaker, then Tidecaller, then Oceanborne (NA). The Burst supplies the lightning you want to trigger during its effect, so start there. Level the Skill next for the counter you use between Bursts.
Leave Normal Attacks until last if Beidou mainly comes in to use her Skill and Burst. Raise them sooner if you prefer keeping her on the field and using her own attacks.
For ascension, collect Noctilucous Jade, Lightning Prism, Vajrada Amethyst Sliver, Vajrada Amethyst Fragment, Vajrada Amethyst Chunk and Vajrada Amethyst Gemstone. You also need Treasure Hoarder Insignia, Silver Raven Insignia, Golden Raven Insignia and Mora.
Constellations worth it
Upon the Turbulent Sea, the Thunder Arises is the first upgrade to look for: Stormbreaker's lightning can jump to two additional targets. That gives it more reach against groups.
Bane of Evil is the next major upgrade. During Stormbreaker, it reduces surrounding opponents' Electro RES by 15%. Sea Beast's Scourge is useful for protection: using the Burst creates a 15-second shield that absorbs up to 16% of Beidou's Max HP and absorbs Electro damage 250% more effectively.
Summoner of Storm and Crimson Tidewalker add three levels to Tidecaller and Stormbreaker respectively. You can leave those talent-level increases for later if you are prioritizing the larger changes to lightning, Electro RES and protection.
Teams
Pair Beidou with a character who can land Normal or Charged Attacks during Stormbreaker. The lightning adds Electro damage, while the effect reduces incoming damage and helps the active character resist interruption.
Common mistakes
Do not hold Tidecaller waiting for two hits every time. A precisely timed counter grants the maximum damage bonus immediately, while a held strike can also build power over time without being attacked. The held shield applies Electro to Beidou, so keep that in mind when choosing your timing.
Do not cast Stormbreaker and then forget its trigger. Make sure Normal or Charged Attacks hit while it is active; repeated hits cannot produce more than one lightning discharge per second.
Do not ignore Energy Recharge when choosing artifacts for a Burst-focused build. Also avoid assuming Thundersoother's four-piece bonus works against every opponent: the target needs to be affected by Electro.
