Updated for Version 2.7
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Table of Contents
Introduction
Having lost his Order, Sunday decided that Harmony was good enough. Taking the field in Honkai: Star Rail as a 5-Star Imaginary character following the Path of Harmony, Sunday provides strong single-target buffs, Action Advance, and excels at lifting up a single ally, allowing them to soar like a Charmony Dove.
Infographic
Credits to: ErisDC, euphorysm, and KQM Staff
Character Overview
Pros
- Enables summons, in addition to characters, to immediately take action.
- Relatively SP efficient even if only using his Skill.
- Potent single-target buffs, especially for characters with summons, and Energy generation.
- Flexible rotations with minimal to no buff downtime.
Cons
- Reliant on his signature Light Cone to guarantee full uptime on his Ultimate and to become SP positive.
- Characters require a summon to get the full benefits of his buffs.
Playstyle
Sunday has one primary gameplan, which is to use his Skill and Ultimate as often as possible on the same target. Following this, Sunday has two playstyles he can choose between: Slow and Fast Skillspam. Which one to pick depends on the team’s SP efficiency and the investment required to hit the targeted SPD thresholds.
With Slow Skillspam, Sunday aims for a SPD slightly slower than his target, effectively doubling their actions by immediately Advancing Forward their next turn after they act.
Fast Skillspam instead replaces the target’s SPD with Sunday’s own, allowing them to focus solely on offensive stats in their own builds. This playstyle is also less SP intensive than a Slow Skillspam Sunday.
For a more detailed breakdown of these playstyles it is recommended to check out the Playstyles section in the KQM Bronya Guide.
Traces
Basic ATK | Gleaming Admonition
Trace Description
Gleaming Admonition [Single Target]
Deals Imaginary DMG equal to 50%/100%/110% of Sunday’s ATK to one designated enemy.
A standard Basic ATK, never worth using as it generates lower Energy than his Skill.
Skill | Benison of Paper and Rites
Trace Description
Benison of Paper and Rites [Support]
Enables one designated ally character and their summon to immediately take action, and increases their DMG dealt by 15%/30%/33%. If the target has a summon, then the dealt DMG increase is further boosted by an additional 25%/50%/55%, lasting for 2 turn(s).
After using Skill on The Beatified, recovers 1 Skill Point.
When Sunday uses this ability on characters following the Path of Harmony, cannot trigger the “immediate action” effect.
Causes the target to immediately act after Sunday. If they possess an active summon, the summon will be Advanced to act after the targeted character, regardless of their relative position beforehand.
If the target has a summon, the DMG% buff takes full effect on both the summon and the target character.
The SP restoration effect refunds 1 Skill Point and will trigger effects that require SP to be restored.
Ultimate | Ode to Caress and Cicatrix
Trace Description
Ode to Caress and Cicatrix [Support]
Regenerates Energy by 20% of Max Energy for one designated ally character, and turns the target and their summon into “The Beatified.” “The Beatified” have their CRIT DMG increased by an amount equal to 12%/30%/33.6% of Sunday’s CRIT DMG plus 8%/12%/12.8%.
At the start of Sunday’s each turn, the duration of “The Beatified” decreases by 1 turn, lasting for a total of 3 turn(s). And it only takes effect on the most recent target of the Ultimate (excluding Sunday himself). When Sunday is knocked down, “The Beatified” will also be dispelled.
While it does provide a decent damage increase, this ability is primarily notable for its Energy regeneration, while being required for Sunday’s Skill’s SP refund to take effect.
As this ability’s duration is based on Sunday’s own turns, he can keep this buff up permanently if he is able to generate enough Energy to use his Ultimate once every 3 of his own turns.
Talent | The Sorrowing Body
Trace Description
The Sorrowing Body [Support]
When using Skill, increases the target’s CRIT Rate by 10%/20%/22%, lasting for 3 turn(s).
Provides an effectively permanent CRIT Rate buff. Due to its 3-turn duration, this will always be active, even for out-of-turn attacks performed when Sunday is running a slower SPD playstyle.
Technique | The Glorious Mysteries
Trace Description
The Glorious Mysteries [Support]
After this Technique is used, the first time Sunday uses an ability on an ally target in the next battle, the target’s DMG dealt increases by 50%, lasting for 2 turn(s).
Makes Sunday’s first Skill more potent, especially useful when content can be cleared quickly.
Ascension 2 Bonus Ability | Rest Day’s Longing
Trace Description
Rest Day’s Longing
When using Ultimate, if the Energy regenerated for the target is less than 40, increases the regenerated Energy to 40.
Makes Sunday’s Ultimate restore 40 Energy to targets with 200 or less Max Energy. This is a significant bonus which can help many characters use their Ultimates more often.
Ascension 4 Bonus Ability | Exalted Sweep
Trace Description
Exalted Sweep
When battle starts, Sunday regenerates 25 Energy.
This Energy is affected by ERR, and can allow Sunday to use his Ultimate after 1 use of his Skill.
Ascension 6 Bonus Ability | Haven in Palm
Trace Description
Haven in Palm
When using Skill, dispels 1 debuff(s) from the target.
Allows Sunday’s Skill to cleanse debuffs that may otherwise prevent his target from acting after being Advanced.
Note: Trace levels shown are 1/10/12 (Basic ATK 1/6/7).
Trace Priority
= =
Talent = Ultimate = Skill
Sunday’s Ultimate, Talent, and Skill all improve his buffing capability, and should all be leveled as much as possible.
As the Ultimate’s CRIT DMG boost scales on Sunday’s CRIT DMG, it can provide the largest stat value per level when highly invested, and should be prioritized first.
Sunday’s Talent provides a fixed increase per level, and is a solid and consistent boost for all characters.
Sunday’s Skill’s value can vary depending on if his target has a summon or not, and hence has the most variable increase of his abilities, but it should still be leveled when possible.
Sunday’s Basic ATK can be ignored.
Eidolons
Eidolon 1 | Millennium’s Quietus
Eidolon Description
When Sunday uses Skill, the target character can ignore 16% of enemy target’s DEF to deal DMG and their summon can ignore 40% of enemy target’s DEF to deal DMG, lasting for 2 turn(s).
Further enhances Sunday’s Skill, allowing the target to ignore a small amount of the enemy’s DEF. However, when the target does damage through a summon, this effect becomes extremely potent, and is one of the strongest damage increases provided by a single Eidolon.
Unlike his Skill, this Eidolon checks if the attack in question is dealing damage through a summon to apply its DEF Ignore effect.
Eidolon 2 | Faith Outstrips Frailty
Eidolon Description
After the first use of Ultimate, recovers 2 Skill Point(s). The DMG dealt by “The Beatified” increases by 30%.
Allows Sunday to provide a burst of SP using his first Ultimate, and slightly increases its buffing capabilities.
This Eidolon is primarily useful when battles can be concluded quickly using the additional SP provided.
Eidolon 3 | Hermitage of Thorns
Eidolon Description
Ultimate Lv. +2, up to a maximum of Lv. 15.
Basic ATK Lv. +1, up to a maximum of LV. 10.
Slightly improves the CRIT DMG provided by Sunday’s Ultimate, but is not notable otherwise.
Eidolon 4 | Sculpture’s Preamble
Eidolon Description
When the turn starts, regenerates 8 Energy.
This Eidolon is simple, yet can enable some unique rotations. On its own, it allows Sunday to use his Ultimate every 3 turns with any Light Cone, and with sufficient external Energy, or his signature Light Cone at a high superimposition, it can allow him to use his Ultimate every 2 turns.
Eidolon 5 | Paper Raft in Silver Bay
Eidolon Description
Skill Lv. +2, up to a maximum of Lv. 15.
Talent Lv. +2, up to a maximum of Lv. 15.
Further buffs to Sunday’s Skill and Talent. Nice QoL, but not particularly notable.
Eidolon 6 | Dawn of Sidereal Cacophony
Eidolon Description
The Talent’s CRIT Rate boost effect becomes stackable up to 3 time(s), and the Talent’s duration increases by 1 turn(s).
When Sunday uses Ultimate, can also apply the Talent’s CRIT Rate boost effect to the target.
When the Talent’s CRIT Rate boost takes effect and the target’s CRIT Rate exceeds 100%, every 1% of excess CRIT Rate increases CRIT DMG by 2%.
Sunday’s final Eidolon allows him to further increase the target’s CRIT stats without worrying about “overcapping” CRIT Rate.
The Talent duration increase, however, isn’t particularly valuable.
Build
Light Cones
 A Grounded Ascent | Sunday’s signature Light Cone provides everything Sunday could want. It enables consistent 3-turn Ultimates when paired with an ERR Rope, allowing Sunday to keep permanent uptime of his Ultimate’s effects. This increases his SP efficiency, which is further improved by the Light Cone’s SP restoration effect, even allowing Sunday to become SP positive. The ramping DMG% buff provided by this Light Cone is the cherry on top, cementing his signature’s position as his BiS. |
 But the Battle Isn’t Over | Provides a slight amount of ERR, allowing Sunday to perform 3-turn Ultimate rotations with only a small amount of external Energy. This Light Cone also provides a potent buff to the target of his Skill, while slightly increasing his SP efficiency. At Superimposition Rank 3, and paired with an ERR Planar, But the Battle Isn’t Over can allow Sunday to perform consistent 3-turn Ultimate rotations. |
 Past and Future | A solid F2P Light Cone, particularly for a Fast Skillspam playstyle, providing a decent 1-turn buff to the target of Sunday’s Skill. |
 Earthly Escapade | Increases Sunday’s CRIT DMG buff from his Ultimate. Sunday’s Skill’s SP refund allows him to generate Radiant Flame stacks, allowing him to periodically refresh the Mask buff. If Sunday can obtain sufficient external Energy to keep full uptime on his Ultimate, Sunday is able to keep permanent uptime on the Mask effect of this Light Cone as well. |
 Dance! Dance! Dance! | With careful SPD tuning, Dance! Dance! Dance! can provide additional actions to the entire team. This is primarily useful when attempting to clear content in as few cycles as possible. |
 Planetary Rendezvous | When running a Slow Skillspam playstyle with an Imaginary-Type damage dealer, Sunday can opt to run this Light Cone to provide some buffs during both their turns that Light Cones such as Past and Future would not be able to. |
Relics
Relic Sets
| Any Pieces with Sufficient SPD | Hitting the desired SPD threshold on Sunday is more important than any individual Set Effect, as additional turns will generally beat out slightly more potent buffs. Set Effects that provide SPD can help Sunday achieve this goal, but are not necessary. |
 4-Pc Sacerdos’ Relived Ordeal | This set provides a SPD boost, making it easier to hit Sunday’s desired SPD, and an easy to trigger CRIT DMG buff. As this CRIT DMG buff only lasts for 2 turns, it can lose uptime if Sunday’s Ultimate is not available frequently enough when running a Slow Skillspam playstyle, making it difficult to keep uptime on 2 stacks of the buff. |
 4-Pc Eagle of Twilight Line | Eagle of Twilight Line is primarily useful for a Fast Skillspam playstyle, being a decent effective SPD increase. |
Planar Ornaments
 Lushaka, the Sunken Seas | Sunday appreciates the ERR provided by this set, and primarily excels in buffing 1 target. This makes Lushaka a perfect fit for Sunday, being both a great benefit to himself and the damage dealer of the team. |
 Broken Keel | Sunday’s 18% Effect RES from his Stat Bonus Traces allows him to activate Broken Keel’s passive with a single Effect RES substat. The CRIT DMG also synergizes well with his Ultimate, slightly increasing the CRIT DMG it can provide. |
| Other Buffing Planars | Sunday can easily hold any other supportive Planar set if the team he is used in would appreciate a different supportive effect instead. |
 Sprightly Vonwacq | If the ERR is required for a faster Ultimate rotation, and the Action Advance helps Sunday take more actions allowing for a faster clear, this set can be considered. If the Action Advance is not required, this set is generally outperformed by Lushaka, the Sunken Seas. |
 SPD Planars | Planar sets that provide SPD as a Set Effect can be run if they are required to hit Sunday’s SPD threshold. |
Stats
 Body |  Boots |  Sphere |  Rope |
| CRIT DMG | SPD | DEF / HP | Energy Regeneration Rate |
Substats
SPD (until breakpoint) > CRIT DMG > DEF% = HP%
Sunday primarily builds SPD until he reaches the threshold for his desired playstyle; either slower than, but as close as possible to his target’s SPD for a Slow Skillspam playstyle, or as much as possible for a Fast Skillspam playstyle.
Refer to the KQM Bronya Guide for further details on these playstyles.
After Sunday’s SPD goal has been reached, any further investment should go towards CRIT DMG to increase the CRIT DMG buff provided by his Ultimate.
If survivability is a concern, defensive stats can be looked for after his SPD threshold has been hit.
Sunday appreciates an ERR Rope to maximize his Ultimate uptime, both to increase his SP efficiency and buff uptime.
Notable Synergies
Damage Dealers
 Argenti | Argenti appreciates Sunday’s ability to generate Energy through his Ultimate and Action Advance. This allows Argenti to use his own Ultimate significantly more frequently, enabling him to trim hordes of enemies down to size. Recommended Sunday Playstyle: Fast Skillspam | ||
 Blade | Blade consumes very little SP on his own, and highly appreciates the additional turns Sunday provides. This allows Blade teams to run supports who can make good use of the extra Skill Points to provide additional utility and refresh buffs more often. | ||
 Dan Heng • Imbibitor Lunae | Providing solid buffs and Action Advance, Sunday is able to replace Imbibitor Lunae’s SPD Boots without straining the team’s SP too much. However, without A Grounded Ascent, his SP efficiency is not as good as Sparkle’s. Sunday is also particularly potent when paired with an E2 Imbibitor Lunae, as his buffs all last for 2 turns or more, allowing Imbibitor Lunae to benefit from them, even during his additional turn. Recommended Sunday Playstyle: Slow Skillspam or Fast Skillspam | ||
 Jing Yuan | Sunday’s Skill Advancing summons allows Jing Yuan to bypass Lightning-Lord’s primary weakness of its low SPD. This allows Jing Yuan to significantly increase his damage, as well increase the flexibility of his rotations. Recommended Sunday Playstyle: Slow Skillspam or Fast Skillspam | ||
 Boothill | Boothill greatly appreciates Sunday’s ability to double his actions, which allows him to accumulate Pocket Trickshot stacks faster, significantly increasing the rate of his Toughness Reduction, and allowing him to trigger his Talent more often against Weakness Broken targets. Sunday’s Energy restoration is also greatly appreciated by Boothill, allowing him to use his Ultimate more often to implant Physical Weakness, as well as increase his Toughness Reduction. Recommended Sunday Playstyle: Slow Skillspam | ||
 Jingliu | Sunday’s Action Advances allow Jingliu to enter her Spectral Transmigration state more frequently. Her low SP consumption paired with Sunday’s own SP efficiency allows her to run more SP-extensive teammates such as Huohuo even while maintaining a Slow Skillspam Sunday. His Ultimate’s Energy restoration can occasionally extend Jingliu’s Spectral Transmigration state by enabling her to use her Ultimate an additional time during it. Recommended Sunday Playstyle: Slow Skillspam | ||
 Topaz & Numby | While Topaz does not benefit as much from Sunday as other summon damage dealers, Sunday can still grant Numby additional actions and significantly increase their damage. Notably, Topaz’s Skill counts as damage dealt by a summon for the purposes of Sunday’s E1. Recommended Sunday Playstyle: Slow Skillspam | ||
 Yunli | Yunli’s high Max Energy allows her to gain 48 Energy per Sunday’s Ultimate, almost granting her half an Ultimate usage with each cast. In addition, Sunday’s CRIT Rate and CRIT DMG buffs pair well with Yunli’s innate CRIT DMG modifiers and further increases her damage. Sunday’s high buff durations also mean Yunli is able to have full uptime on his buffs. Recommended Sunday Playstyle: Fast Skillspam | ||
| Other Damage Dealers | Sunday can provide significant benefits to any damage dealer who appreciates the extra actions he can provide, especially if they can take full advantage of his Energy restoration as well. | ||
Other Characters
 Lingsha | Sunday’s ability to Advance Fuyuan can allow Lingsha to take on a potent damage dealer role, utilizing either Super Break enablers, like Imaginary Trailblazer, or characters who appreciate frequent attacks, like Jade, to inflict significant AoE damage. When Lingsha is used as a general healer, Sunday can in a pinch use his Skill on Lingsha to advance Fuyuan for a larger burst heal. Recommended Sunday Playstyle: Slow Skillspam | ||
 Huohuo | Sunday’s SP efficiency allows Huohuo to use her Skill more often to keep the team healthy, while their paired Energy restoration abilities can allow their teams to use their Ultimates significantly more frequently. | ||
 Bobin | Robin’s potent buffs during Concerto combined with Sunday’s low SP consumption can allow Sunday to continuously Advance the damage dealer during Robin’s Ultimate, allowing the damage dealer to easily get 4+ buffed actions during one Robin Ultimate. Sunday can also use his Ultimate to charge Robin’s Ultimate faster, but this is not recommended unless the team’s SP generation can support Sunday consuming significant SP. | ||
Special Considerations
 Bronya | While Sunday is unable to Action Advance other Harmony characters, the reverse is not true for Bronya. Bronya can Advance Sunday, who can then Advance the damage dealer once again. While this setup means the damage dealer does not benefit from Bronya’s Skill buff, it allows Sunday to Advance summons twice as often. Additionally, if Sunday has his signature Light Cone, the team will generate more SP if Bronya Advances Sunday than if she Advances the damage dealer. | ||
Teams
Slow Skillspam
These teams take advantage of Sunday’s complete Action Advance to double the damage dealer’s actions by running Sunday slightly slower than them. Due to the potential high SP consumption of this playstyle, SP-positive supports and sustains can be appreciated.
Example Teams
Taking full advantage of Sunday’s Action Advance and SP efficiency, this team can consistently get 7+ Lightning-Lord Hits Per Action at a high frequency. This is achieved through Jing Yuan using his Skill once, then Sunday Advancing him to use his Skill again before the Advanced Lighting-Lord acts.
Robin further buffs the damage of this team, but does not contribute much SP, so Ruan Mei can instead be an option with solid buffs and higher SP generation. Gallagher helps feed the SP demands of this team.
Argenti greatly appreciates the Energy provided by this team, while Sunday allows him to stack his Talent faster and provides a strong CRIT DMG buff to go along with Argenti’s innate CRIT Rate buffs. If SP is not an issue, Huohuo can be run over Gallagher for even more Energy.
Jingliu’s and Sunday’s high SP efficiency allows this team to rapidly charge Jingliu’s Ultimate to consistently extend her Spectral Transmigration state. If more SP is required, Pela can be a substitute for Tingyun while providing potent debuffs.
Sunday is used to double Boothill’s actions, significantly increasing his damage output and Toughness Reduction abilities. This is further amplified by Ruan Mei’s Weakness Break Efficiency, ensuring that Boothill can rapidly inflict Weakness Break on any enemy, and topped off with Gallgher or Lingsha’s Break DMG Vulnerability debuffs.
Sunday’s SP efficiency can allow Lingsha to function in this team, which is appreciated in AoE content that has a Weakness to Fire.
A team composed of only permanently available characters. Sunday can easily enable Dan Heng’s Wind RES PEN Talent, being able to trigger it even outside of Sunday’s turn by using his Ultimate. Yukong is especially potent if her E6 is unlocked, allowing her to use her Skill before Dan Heng’s turn, then using her Ultimate during Sunday’s turn to provide a further buff to Dan Heng’s next turn.
Fast Skillspam
These teams aim to replace the damage dealer’s SPD stat with Sunday’s. These teams can take advantage of Sunday’s SP efficiency to run more SP-intensive supports, especially if Sunday is equipped with A Grounded Ascent.
Example Teams
Imbibitor Lunae’s high SP consumption makes a Fast Skillspam playstyle with Sunday the most beneficial for him. Sunday and Tingyun can provide Energy to fuel Imbibitor Lunae’s Ultimate, which can further improve his SP efficiency, while Ruan Mei can provide potent buffs that are not tied to Imbibitor Lunae’s turns if he has his E2 unlocked.
Yunli’s high Max Energy allows Sunday to restore almost half an Ultimate usage for her on every use of his Ultimate. Paired with Tingyun’s potent buffs and Energy restoration and Lynx’s aggro modifier makes this an excellent team to maximize the number of Counters Yunli can perform.
While technically a Fast Skillspam playstyle, Bronya is run slightly slower than Sunday to Advance Sunday, which allows Sunday to Advance Jing Yuan and Lightning-Lord again. This team maximizes the number of Lightning-Lord actions in exchange for a lower number of Hits Per Action.
This is an extremely SP-intensive team, so Jing Yuan may be occasionally forced to use his Basic ATK, even with Gallagher’s potent SP generation.
Credits
Authors
soul_fish
Editors
happy_ice_cream
Ley
skylarke
Publishers
nyte
Changelog
- 02 January 2025 – Published for v2.7