Gallagher Quick Guide

Updated for Version 2.5

Note that the information given may change if new discoveries are made. More extensive testing is in progress.

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Introduction

Gallagher is a 4★ Fire Abundance healer in Honkai: Star Rail who specializes in increasing Break DMG, debuff application, and high SP generation. He is the best 4★ Abundance in terms of raw healing, the best SP generator amongst sustain units, and the most consistent Abundance unit at debuffing enemies as of Version 2.4. This quick guide will help you with his best Relics, Light Cones, teams, synergies, and more!

New Content

Scent Alone Stays True

Gallagher’s general BiS. The major selling point of this Light Cone is its 18% Vulnerability, which provides universal damage amplification. Its 150% Break Effect threshold is easy to reach, especially with the extra Break Effect, and happens to max out Gallagher’s A2 healing conversion. It also inflicts a debuff, which is appreciated by units such as Dr. Ratio and units utilizing 2-Pc or 4-Pc Pioneer Diver of Dead Waters. An excellent choice for any team.

4-Pc Passerby of Wandering Cloud

While its use case is niche, Gallagher is able to take advantage of 4-Pc Passerby of Wandering Cloud’s Outgoing Healing Bonus and extra SP at the start of the battle, which can be helpful in teams with SP-hungry units. However, in many situations, the extra SP is redundant, as E1+ Gallagher can already provide an extra SP with his post-Ultimate Advance. Farming a specific 4-Pc set sacrifices the opportunity to pick Relics with better stats, and forces you to farm specifically for Gallagher instead of your damage dealer(s).

Character Overview

Playstyle

Gallagher’s primary goal is to maintain Ultimate uptime. His secondary goal is to do this with as much SP gain as possible. 

Traces

Note: Trace levels shown are 1/10/12 (Basic ATK 1/6/7).

Trace Priority

Gallagher’s healing only scales on Trace levels. The majority of it is in his Talent, which also includes his Break DMG increase.

Gallagher’s Skill is his other source of healing, although less frequent. It does not need to be fully leveled, as even at lower levels, it is capable of overhealing allies.

Upgrading Gallagher’s Basic ATK can improve his ATK reduction debuff, but this is rather insignificant and does not need to be leveled at all.

Leveling his Ultimate only improves his paltry ATK-scaling damage, so can be ignored.

Eidolons

Build

Light Cones

Scent Alone Stays True	Gallagher’s general BiS. The major selling point of this Light Cone is its 18% Vulnerability, which provides universal damage amplification. Its 150% Break Effect threshold is easy to reach, especially with the extra Break Effect, and happens to max out Gallagher’s A2 healing conversion. It also inflicts a debuff, which is appreciated by units such as Dr. Ratio and units utilizing 2-Pc or 4-Pc Pioneer Diver of Dead Waters. An excellent choice for any team.
Echoes of the Coffin	Enables a 3-turn Ultimate with a 5% ERR planar, granting permanent Besotted uptime before E4. More frequent Ultimates and Enhanced Basic ATKs help both Gallagher’s Breaking and his ability to sustain allies who usually do not attack the enemy, such as Bronya and Sparkle.
Night of Fright	Enables a 4-turn Ultimate using only Basic ATKs with the help of an Energy Regeneration Rate rope. Its healing on Ultimate use helps units that do not attack the enemy, but not as well as Echoes of the Coffin.
Multiplication	Gallagher’s best choice for SPD and SP generation. He attacks four times in the time it usually takes for three, often resulting in the same Ultimate uptime as other options while generating more SP. Although he does not receive an Advance from Multiplication when he uses his Skill, if his Ultimate is used directly afterwards, he does not lose any effective SPD. However, if Gallagher uses his Skill frequently, he is unable to take full advantage of this Light Cone.
Post-Op Conversation	Post-Op Conversation’s main utility lies in its Energy Regeneration Rate. At S2+ with an ERR rope, it enables a fully SP-positive 4-turn Ultimate. S5 allows Gallagher to run a Break Effect Rope with no loss in Besotted uptime, as well as giving him more Break Effect than S5 What is Real?.  Gallagher cannot directly utilize its Outgoing Healing Bonus, but all units who attack a Besotted enemy with their own Ultimate benefit from it.
Quid Pro Quo	Gallagher can exploit this Light Cone well due to his frequent actions. While it does not help with his healing, the Energy can prove extremely useful in some setups, such as Robin teams, but won’t always be impactful.
Perfect Timing	Synergizes with Gallagher’s E1; essentially grants debuff immunity as well as a massive Outgoing Healing Bonus stat. However, Light Cones with stronger supportive utility are recommended over this one.
What is Real?	This cone provides a small Break Effect Bonus (which converts to Outgoing Healing Bonus). However, Light Cones with stronger supportive utility are recommended even in Super Break teams.

Relics

Relic Sets

Any	No set should be farmed specifically for Gallagher himself. Instead, use whatever Relics are available for his best overall stats, even if it means not completing any set bonuses.  All set bonuses can be plausibly beaten by superior substats; 2-Pc Messenger Traversing Hackerspace can be replaced by 5.88 SPD, 2-Pc Break Effect sets are worth 16% Break Effect, and 2-Pc Passerby of Wandering Cloud is the equivalent of 20% Break Effect for Gallagher’s healing.
4-Pc Iron Cavalry Against the Scourge	Gallagher’s preferred option for Super Break teams to maximize his own Super Break DMG. 2-Pc sets are very poor substitutes. Extremely weak outside of Super Break.
4-Pc Passerby of Wandering Cloud	While its use case is niche, Gallagher is able to take advantage of 4-Pc Passerby of Wandering Cloud’s Outgoing Healing Bonus and extra SP at the start of the battle, which can be helpful in teams with SP-hungry units. However, in many situations, the extra SP is redundant, as E1+ Gallagher can already provide an extra SP with his post-Ultimate Advance. Farming a specific 4-Pc set sacrifices the opportunity to pick Relics with better stats, and forces you to farm specifically for Gallagher instead of your damage dealer(s).

Planar Ornaments

Lushaka, the Sunken Seas	The best buff for most ATK-scaling hypercarry teams by a small margin. It remains useful in teams with multiple damage dealers. The Energy Regeneration Rate is only helpful in specific setups.
Broken Keel	CRIT DMG buffs are useful in the right teams, and Gallagher activates this one for free.
Penacony, Land of the Dreams	When Gallagher is paired with a Fire-Type damage dealer who is not a Break DMG unit, this is the best buff available. The extra Energy Regeneration Rate is not usually significant.
Fleet of the Ageless	While not as much of a buff as the other supportive sets, the ATK% buff is almost universally appreciated by damage dealers.
Forge of the Kalpagni Lantern	Although the extra Break Effect is nice for Gallagher’s healing when he can activate it, this set’s real use is in its extra SPD, which is difficult to get elsewhere. Does not see much use outside of Firefly teams, as otherwise you would prefer a more supportive set.
Talia, Kingdom of Banditry	Best-in-Slot for Super Break when enemies do not have a Fire Weakness. If 145 SPD is reached, it provides 16% Outgoing Healing Bonus. Not very helpful outside of Super Break, since you sacrifice the opportunity to use a more supportive planar.
Sprightly Vonwacq	Not very useful. Gallagher should not need this set to act before your damage dealer. The Energy Regeneration Rate is only useful in niche scenarios.

Stats

Body	Boots	Sphere	Rope
Outgoing Healing Bonus	SPD	HP / DEF	Energy Regeneration Rate > Break Effect

Substats

SPD > Break Effect (until 150%*) > Effect RES (until 100% in combat) > HP% ≥ DEF%

*Unless in a Super Break team, in which case there should be no limit.

Break Effect Rope vs. Energy Regeneration Rate Rope

When utilizing Light Cones with Energy generation, an Energy Regeneration Rate Rope should be used to take advantage of it, unless the Light Cone is S5 Post-Op Conversation.

If using Multiplication, a Break Effect rope can be used without losing Ultimate frequency. Although it takes 5 turns to get Gallagher’s Ultimate back, this takes the same amount of AV as 4 turns with another Light Cone. 

If neither of these conditions apply, an Energy Regeneration Rate Rope allows for 4-turn Ultimates, while a Break Effect Rope allows for 5-turn ones. Take your pick. 

Energy Breakpoints

Light Cone	Rope (+15)	5% ERR Planar	Rotation (Actions per Ultimate)
Any	Break Effect	Yes	5 Basic ATKs	–
Any	Break Effect	No	4 Basic ATKs	1 Skill
S2+ Post-Op Conversation	ERR	No	4 Basic ATKs	–
Night of Fright	ERR	No	4 Basic ATKs	–
Any	ERR	No	3 Basic ATKs	1 Skill
S5 Post-Op Conversation	Break Effect	No	3 Basic ATKs	1 Skill
Echoes of the Coffin	ERR	Yes	2 Basic ATKs*	1 Skill

Notable Synergies

Damage Dealers

Break DMG units: Firefly, Boothill	Effects that improve Break DMG are rare, and Gallagher is both a healer and a debuffer, which allows for efficient role compression.
Acheron	Gallagher applies one debuff on his Ultimate, and one debuff with the Enhanced Basic ATK after his Ultimate. His excellent SP generation allows for more SP-negative playstyles by Acheron’s teammates.
Dr. Ratio	Gallagher improves Dr. Ratio’s follow-up chance, as he provides one debuff on his Ultimate, and one debuff with the Enhanced Basic ATK, which is two-thirds of the way to a 100% chance. Gallagher can also frontload the damage from Wiseman’s Folly to take advantage of short-lived buffs such as Bronya’s Skill, as his Ultimate and subsequent Enhanced Basic ATK can be two consecutive attacks in the span of 0 AV.
Himeko	Gallagher’s excellent Weakness Breaking abilities can quickly generate points of Charge for Himeko. He is always relevant for her due to their shared Type, as any scenario in which Himeko can Weakness Break, so can Gallagher.
March 7th (The Hunt) / Jade	Gallagher attacks frequently, which means that he generates stacks for Jade/March frequently. The extra SPD buff he receives from them is helpful for this purpose. He is especially useful when either a Weakness Break or frequent but weak attacks are preferred.

Buffer

Ruan Mei	Ruan Mei improves Gallagher’s ability to sustain directly with her Break Effect buff, and indirectly with her Weakness Break extension, as Weakness Broken enemies cannot attack. Her Weakness Break Efficiency buff also boosts Gallagher’s already excellent ability to take down Toughness bars, which improves team sustain further through faster and more frequent Weakness Breaks.
Imaginary Trailblazer	In Super Break teams, Gallagher can significantly contribute offensively, defensively, and supportively. His Toughness DMG accelerates the start of the Super Break damage window, and as he builds a lot of Break Effect, he deals a considerable amount of Super Break DMG himself. He also provides good role compression as he is both a healer, debuffer, battery for his teammates with his SP generation, and can improve Super Break DMG with his Break DMG Vulnerability.
Robin	Due to Gallagher’s frequent actions, he often triggers Robin’s Energy generating Talent and her Ultimate’s Additional Physical DMG. He is also able to use Quid Pro Quo to further aid her Energy generation. However, Robin’s sparse number of attacks prevent her from taking advantage of the majority of Gallagher’s healing, and you may need to use his Skill on her.

Special Considerations

Counter Units: Yunli, Clara	Gallagher has excellent Toughness DMG. If enemies are Weakness Broken more often, they attack less, which reduces the amount of Counters.
Units with Infrequent Attacks: Bronya, Sparkle, Robin	Units who attack infrequently or not at all cannot take advantage of Gallagher’s Talent healing, and can only be healed through his Skill and enhanced Basic ATK. As Gallagher has terrible one-shot protection and Emergency healing, this issue is further amplified.

Teams

General Sustain

Due to Gallagher’s SP positivity, he can be played in any team as an offensive sustain pick and SP generator. His Break DMG increase allows for some extra chip damage. 

Example Teams

Gallagher contributes up to two debuffs for Dr. Ratio, while Pela can easily make up the rest. Gallagher’s SP positivity allows flexibility in Robin and Pela’s SP usage. As Robin’s Energy situation can be quite dire, Gallagher should be played with Quid Pro Quo to help her as much as possible.

Gallagher’s high SP generation combined with Sparkle’s SP generation fuels Imbibitor Lunae’s 3x Enhanced Basic ATKs. Gallagher can equip Multiplication for maximum SP generation. 

Kafka and Black Swan will always attack, which leads to more healing from Gallagher’s Talent. Gallagher’s SP-positivity lets Black Swan use her Skill more frequently, which improves her Talent damage in AoE scenarios and allows her to recharge her Ultimate faster.

Gallagher Breaks enemies quickly, allowing the team to take advantage of Ruan Mei’s Weakness Break extension, which causes Broken enemies to act more frequently than even enemies that were never Broken.

Break Damage Support

As an Abundance unit and one of the few sources of Break DMG increases, Gallagher is both a debuffer, a healer, and sometimes a “damage dealer”. The support unit should be able to buff Break DMG, the best choice by far being Ruan Mei. 

Example Teams

A strong 4★ only team if the enemy is weak to Imaginary and/or Fire. All units should be built with as much SPD and Break Effect as possible. March 7th should designate Gallagher as her Shifu, which gives her increased Toughness reduction. Gallagher quickly generates stacks, allowing March to use her Enhanced Basic ATK more frequently. Once enemies are Weakness Broken, Asta’s SPD buff as well as all units’ high number of hits will result in some considerable Super Break damage. 

A fairly straightforward team that relies on Gallagher’s SP generation to allow Bronya to be played with the Slow Skillspam playstyle. Multiplication is an excellent Light Cone to equip since it amplifies Gallagher’s SP-positivity. 

For more information about Bronya’s playstyles, check out KQM’s Bronya Guide.

Gallagher helps Firefly Break faster and buffs her Super Break DMG. His SP positivity allows Imaginary Trailblazer to use their Skill more often for even more damage. Ruan Mei provides buffs and an improvement to teamwide sustain. Forge of the Kalpagni Lantern will always have its Break Effect buff active in this team.

Credits

References

Gallagher Energy by skylarke

Changelog

• 2 October 2024 – Updated for v2.5
• 10 September 2024 – Added Lushaka, the Sunken Seas to recommended planars.
• 9 September 2024 – Published for v2.4