This post is up to date with Version 3.1 Phase 2
Nilou is a 5-Star Hydro Sword character from Sumeru. She can only be obtained via the “Twirling Lotus” event banner. Primarily, she serves as either a Main DPS or a Sub DPS with a penchant for the Bloom Elemental Reaction.
Base Kit
Nilou is the first ever character with the ability to modify an Elemental Reaction. When Nilou’s team consists of only Hydro and Dendro characters, with at least one in each Element, her A1 passive becomes active. With this passive, a full cast of Nilou’s Elemental Skill (more on that in a bit) will grant her team the Golden Chalice’s Bounty for 30 seconds. Characters under this effect can buff their team by 100 Elemental Mastery when they are hit by Dendro DMG (including the self DMG caused by Bloom). Triggering Bloom will also create Bountiful Cores instead of the standard Dendro Cores. These can’t be used to trigger Hyperbloom or Burgeon but possess a quicker explosion and a larger AoE as tradeoffs. Bountiful Cores can be modified further with Nilou’s A4 passive, giving them a 9% DMG increase for every 1,000 points of Nilou’s Max HP above 30,000. The DMG increase caps at 400%. Both Nilou’s Elemental Skill and Elemental Burst scale off of HP so building her with HP for her A4 passive should not prove to be an issue.
The requirement to only use Hydro and Dendro characters to gain access to these modifiers does make Nilou a restrictive unit to use optimally. Hydro does have eight other characters for you to consider though not of all them benefit from the Element’s Resonance effect. Dendro meanwhile only has three, four once Nahida releases in Version 3.2, so your pickings there are even slimmer. There currently does not exist a Dendro healer so you’re forced to look towards Hydro for that department. Neither Hydro nor Dendro has a shielder so that’s entirely off the table. The team comp restriction may become less of an issue as more Hydro or Dendro characters are added into the game but that’s entirely up to miHoYo to do. As it stands, you have just a few options to consider for a Nilou Bloom team, especially if you’re F2P.
In spite of the restriction, I really like using Nilou for Bloom. The idea that a character can alter an Elemental Reaction has a lot of potential in making them more unique as well as keep Genshin‘s meta afresh. Novelty aside, Nilou’s Bloom modifiers does have the DMG to back them up. Provided that she’s built with a lot of HP, Nilou can crank up the base DMG of Bloom by a significant amount before traditional Reaction scaling is factored in. With a full Hydro/Dendro team, you can generate a lot of Bountiful Cores. The decreased time to explode makes up for the lack of Burgeon or Hyperbloom procs. The increased AoE helps your team cover a lot of ground. Even if Nilou herself deals lousy numbers, her DPS is still potentially high thanks to her Bloom modifiers.
When Nilou casts her Elemental Skill, Dance of Haftkarsvar, she deals AoE Hydro DMG based on her Max HP and enters the Pirouette state for 10 seconds. And here is where things get a little complicated. While in Pirouette, using the Attack button or the Skill button will have Nilou perform either Sword Dance or Whirling Steps respectively. Both these stances are a series of three Hydro-infused Normal Attacks that count as Elemental Skill DMG. DMG dealt by either stance is based on Nilou’s Max HP, with Sword Dance possessing higher multipliers than Whirling Steps. You can use either stance interchangeably until Nilou performs the third attack. If you use the Attack button third and have Nilou perform a Sword Dance, she gains the Lunar Prayer effect and is free to continue performing Sword Dance for 8 seconds. If you instead use the Skill button third and have Nilou perform a Whirling Step, she trades her Hydro attacks for a Tranquility Aura for 12 seconds. This Hydro AoE deals no DMG but it does follow your active character and applies Wet to any opponent within its radius. Regardless of how you execute Nilou’s Skill, the overall cooldown it has is 18 seconds.
The great thing about Nilou’s Elemental Skill is that it’s versatile. With it, Nilou can either serve as a carry with Sword Dance or serve as an off field enable with the Tranquility Aura. Using one over the other will generally depend on preference and what works best for your team’s rotation. The Tranquility Aura has better uptime and coverage. However, Sword Dance is the ability that can actually deal DMG and it is Nilou’s second best source of DMG besides her Bloom modifiers. You should consider using it if you don’t have anyone else to act as a carry. Since the third input is what determines which ability you get, you ideally want to do two Sword Dance attacks first and then finish with the desired input as Sword Dance has higher multipliers than Whirling Steps. If you choose to continue with Sword Dance, you want to perform the full three attack combo as the third one hits the hardest. Fortunately, it’s quick and doesn’t have much knockback so there’s no harm in executing it.
For her Elemental Burst, Dance of Abzendengi: Distant Dreams, Listening Spring, Nilou performs a quick dance move that deals a Hydro explosion based on her Max HP at close range. Any enemies hit by the explosion will be inflicted with the Lingering Aeon effect which will cause them to take a second bout of Hydro DMG after a brief interval. It’s a pretty good nuke and it allows you to apply Hydro and proc Bloom in an AoE, for two times even.
Nilou’s Elemental Burst has a cooldown of 18 seconds, making it synchronistic with her Elemental Skill during a rotation. It also has a fairly high cost of 70 Energy. Stacking Energy Recharge can help with this matter though you don’t necessarily need a whole lot. Since she might as well be teamed up with another Hydro unit due to her team comp restriction, Nilou’s Energy needs might not be too high if that teammate has good particle generation. Another thing to note is that while it is nice to cast a nuke every rotation, Nilou’s Elemental Skill is better for sustained Hydro application and/or DPS so you don’t necessarily need to build her for her Burst.
Constellations
- C1 – Enhances Nilou’s Elemental Skill in two ways. The DMG of Nilou’s third Sword Dance attack is increased by 65% while her Tranquility Aura lasts for 6 more seconds. I find it a little odd that only the third Sword Dance attack is buffed but the DMG difference is very noticeable and it makes it more imperative that you perform the full three attack combo. The increased duration for the Tranquility Aura is also very nice; at C1, it now has 100% uptime.
- C2 – Decreases enemy Hydro RES by 35% for 10 seconds after Nilou or someone else deals Hydro DMG while Nilou’s A1 passive is active. When Bloom is triggered, enemies also have their Dendro RES debuffed by the same percent and for the same amount of time. I find this to be Nilou’s best Constellation, providing her with a Hydro RES debuff that is normally provided by an Anemo character equipped with 4-Piece Viridescent Venerer. The Dendro RES debuff also comes in handy if you don’t have someone equipped with 4-Piece Deepwood Memories.
- C3 – Adds three Levels to Nilou’s Elemental Burst.
- C4 – Gives Nilou 15 Energy and increases her Elemental Burst DMG by 50% for 8 seconds after she finishes the Pirouette phase of her Elemental Skill. While the free Energy can lower Nilou’s Burst cost down to 55 and come in clutch when she’s close to getting it back, it is a little strict of the Constellation to get the Energy while also being expected to cast the Burst within 8 seconds. It’d be better if the Energy was gained after the Burst is cast. The same can almost be said about the Burst DMG Bonus. It works fine with the Tranquility Aura as the latter is off field but it becomes an issue with Lunar Prayer. Since the DMG Bonus buff and Lunar Prayer both last 8 seconds, you will lose out on some Sword Dance uptime when you cast your Burst during Lunar Prayer’s duration. Ultimately, this Constellation can be helpful but it’s also very awkward to use.
- C5 – Adds three Levels to Nilou’s Elemental Skill.
- C6 – Gives Nilou 0.6% CRIT Rate and 1.2% CRIT DMG for every 1,000 points of her Max HP; caps out at 30% CRIT Rate and 60% CRIT DMG. For the full effects, Nilou needs 50,000 HP though this is already achievable for a pre-C6 Nilou via Artifacts. The benefit of this Constellation is that it makes it easier to build Nilou with a solid CRIT Ratio without deviating from stacking her HP for her Bloom modifiers. It’s a very nice quality of life improvement and it does allow Nilou to branch out into raw Hydro DPS and other Elemental Reactions. Whether or not it’s worth hundreds of dollars however is a whole other matter.
Overall, I find Nilou’s Constellations to be a pretty good set. But as is always the case for 5-Star characters, you should only consider going after their Constellations if you have the money to burn. Some good stopping points besides C0 and C6 are C1 and (especially) C2.
Weapons
Nilou’s Signature Weapon is the Key of Khaj Nisut. It offers the wielder a ton of HP, 66.2% as its second stat and 20% via its passive (which increases with refinements), totaling to a whopping 86.2% HP increase. With that much HP%, Nilou’s Bloom modifiers and her base personal DMG become significantly stronger. Alternatively, the Key allows Nilou to comfortably trade a HP% Artifact for something else, such as a Hydro DMG Goblet or a CRIT Circlet, without losing too much on Bloom DMG.
The Key of Khaj Nisut is also not just a HP stat stick. With its passive at R1, the Sword can also buff the wielder’s Elemental Mastery by 0.12% of their Max HP for 20 seconds when the wielder hits an opponent with their Elemental Skill. Up to three stacks can be obtained and with all three, the wielder will also buff their teammates’ Elemental Mastery by 0.2% of their Max HP for the same amount of time as the default buff. Since Nilou can strike three times with the Pirouette phase of her Elemental Skill, she can very easily obtain all three stacks back to back. Provided that her Max HP is high, she can buff her team’s Elemental Mastery by the hundreds and subsequently increase her team’s Bloom DMG by a significant amount.
Given that HP is its second stat, the Key won’t be the most universally applicable Sword for your account so some weariness is advised. Nevertheless, it is a very strong weapon to give to Nilou.
Below are some other weapons to consider.
- Primordial Jade Cutter (5-Star) – Provides 44.1% CRIT Rate at Lv. 90. At R1, the passive increases the wielder’s Max HP by 20% and their ATK by 1.2% of their Max HP. This is an extremely tempting alternative to the Key of Khaj Nisut, especially if you feel more inclined to augment Nilou’s personal DMG. For a Pre-C6, a Nilou with Jade Cutter just needs 25.9% more CRIT Rate from Artifacts. At C6, her CRIT Rate is entirely covered before Artifacts are factored in. That said, the Jade Cutter doesn’t provide Nilou enough HP to comfortably replace a HP Artifact with something else and without sacrificing some of her Bloom DPS potential. For both personal DMG and Bloom, I find the Key to be the better pick. There’s also an opportunity cost with the Jade Cutter as other characters such as Keqing would make better use of the weapon’s HP to ATK conversion.
- Favonius Sword (4-Star) – Unfortunately, there is no 3 or 4-Star Sword that increases HP so the next best thing you can do is give Nilou something that’ll raise other stats relevant to her. With Favonius Sword, you’re giving Nilou a lot of Energy Recharge and the chance to generate neutral particles with a CRIT, allowing her to get her Elemental Burst more reliably. Bear in mind that you are going to need a decent CRIT Rate in order to consistently proc the Sword’s passive.
- Festering Desire (4-Star) – Not up for consideration if you didn’t get it way back in Version 1.2’s Flagship Event. Regardless, it is a useful F2P weapon for Nilou’s personal DPS, providing her with Energy Recharge, Elemental Skill DMG, and Skill CRIT Rate.
- Iron Sting (4-Star) – A F2P weapon obtained via Forging. The Iron Sting provides Elemental Mastery as it can boost all of Nilou’s DMG up to two times and for 6 seconds when she deals Elemental DMG. It can be strong but it does skew towards using Nilou as a carry.
- Sacrificial Sword (4-Star) – Another Energy Recharge stat stick; also gives Nilou the chance to reset her Elemental Skill cooldown (and Nilou has a lot of chances to proc it). You are going want this Sword at R5 so that the reset’s cooldown can outpace that of Nilou’s Skill. If the passive procs by the time Nilou gets her Tranquility Aura, she has the opportunity to gain Sword Dance and use both phases simultaneously.
- Xiphos’ Moonlight (4-Star) – Provides Elemental Mastery as well as some Energy Recharge for 10 seconds and for every point of the former stat. It won’t increase Nilou’s HP but it will kill two other birds with one stone.
- Harbinger of Dawn (3-Star) – Provides 46.9% CRIT DMG at Lv. 90. AT R5, the passive gives 28% CRIT Rate so long as the wielder’s HP is above 90%. In theory, this Sword is the best way besides Nilou’s sixth Constellation to build her CRIT Ratio. However, Nilou will need a healer potent and fast enough to keep Nilou’s HP above 90%, be it from enemy attacks or the self DMG caused by Bloom.
Artifacts
There currently does not exist a 4-Piece set tailored to Nilou’s kit so unless miHoYo changes that in the future, I recommend giving Nilou 2-Piece Bonuses that are the most relevant to her. A mainstay is Tenacity of the Millelith (2) as this increases Nilou’s Max HP by 20%. A couple of options exist for the second Bonus. Wanderer’s Troupe (2) or Gilded Dreams (2) can be used to give Nilou 80 Elemental Mastery and this is the only other Bonus that could increase your team’s Bloom DMG. That is however assuming that Nilou is the one triggering Bloom. Alternatively, you can give Nilou Heart of Depth (2) for a 15% Hydro DMG Bonus for slight boost to her personal DMG and for something less conditional than Elemental Mastery. The choice boils down to personal preference and whichever set has better sub stats.
For her three core pieces, Nilou wants HP% as her main stat. A Hydro DMG Bonus Goblet and a CRIT Circlet are better for her own DPS, especially if you’re not using Bloom, but for both her DMG and Bloom, triple HP% is the way to go. Having HP% on all three core pieces will have Nilou at 50,000 Max HP before even factoring in sub stats and/or other sources such as the Key of Khaj Nisut and Hydro Resonance. Therefore, even if your Nilou is at C6, you’re still incentivized to go triple HP%. If you have a R1 Key, you can comfortably use a Hydro DMG Bonus Goblet or CRIT Circlet and still have 50,000 Max HP. If Nilou is also at C6, you should opt specifically for the Goblet.
Sub stats you want to look for are HP%, CRIT Rate, CRIT DMG, Elemental Mastery, and Energy Recharge. Prioritize HP% and Elemental Mastery for further Bloom DMG or CRIT for more personal DMG and a more balanced/universal build. Depending on if you have other Hydro characters and the amount of particles they can generate, you don’t need a lot of Energy Recharge on Nilou. Only Nilou’s Normal Attacks scale off of ATK so you should avoid stacking that stat on her.
Synergy
As mentioned in the Base Kit section, Nilou wants to use Bloom and only Bloom. To gain access to her modifiers, you must only use Hydro and Dendro characters in her team and have at least one for each Element. Broadly speaking, it is best to have two Hydro and two Dendro so that your team has both Elements’ Resonance effects. Hydro Resonance increases your team’s Max HP while Dendro Resonance increases their Elemental Mastery, more so after Bloom is triggered. As you can tell, both buffs are relevant for Nilou and her modified Bloom. That said, you do have the flexibility of running three of one element and one of the other if need be.
Given Nilou’s team comp restriction and for the purpose of streamlining, I won’t suggest any teammates of any other Elements besides Dendro and Hydro. I will however make a brief comment that Nilou can slot into teams involving other Hydro-related Elemental Reactions pretty well, due to her versatile kit and playstyle. Doing so just won’t utilize her to her fullest.
Dendro:
- Traveler (Dendro) (5-Star) – A Dendro Sub DPS that can be obtained for free and a pretty respectable one at that. When it infuses with Hydro, the Traveler’s Elemental Burst gains increased AoE, allowing Nilou’s team to cover a lot of ground. One thing to worry about with the Dendro Traveler is their high Energy needs, especially if they’re the sole Dendro unit on the team.
- Collei (4-Star) – Another Dendro Sub DPS that can be obtained for free. Frankly, I don’t find Collei’s kit to be terribly good, the main issue being the downtime of her Talents. That said, her availability combined with the current lack of Dendro characters available in the game puts her up for consideration.
Hydro:
- Sangonomiya Kokomi (5-Star) – A very versatile unit to team Nilou with. Kokomi can heal. She can serve as the carry in Nilou’s place with her Elemental Burst. Her Elemental Skill ignores Internal Cooldown and can therefore contribute to a lot of Bloom procs with each heal/tick. She can wield Thrilling Tales of Dragon Slayers and 4-Piece Tenacity of the Millelith to buff her Dendro teammates.
- Yelan (5-Star) – Being a Hydro Sub DPS makes Yelan a very contested unit. In particular, she’s a valuable asset to Vaporize team comp. Having Yelan in the same team as Nilou also means you’ll have to reserve a third spot for a Hydro healer and only have one Dendro character in the team. Nevertheless, Yelan is worth considering for her off field DMG and Hydro particle generation.
- Barbara (4-Star) – Currently, the only other healer you can consider. Barbara’s healing isn’t as potent as Kokomi and she’s not as versatile as the latter. She is also the single worst battery unit for Nilou as she can’t generate any particles innately. Nevertheless, Barbara can be obtained for free so she has availability going for herself.
Example Teams:
| Nilou | Barbara | Traveler (Dendro) | Collei |
| Nilou | Sangonomiya Kokomi | Traveler (Dendro) | Collei |
| Nilou | Sangonomiya Kokomi | Yelan | Traveler (Dendro) |
Conclusion
Nilou is a niche character. This is largely due to her Hydro & Dendro only requirement making her inflexible for building a team around and leaving her with very few teammates to consider. Gearing her is also tricky due to the lack of a HP-oriented Sword below 5-Stars and the lack of a 4-Piece Artifact set that’s tailored to her kit. That all said, Nilou is still a strong and fun character to use thanks to her unprecedented and potentially strong modifiers for Bloom. So long as you play along with her demands, she’ll clear content just fine.
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