Updated for Version 4.3

Thoma is a 4-star Pyro Polearm character in Genshin Impact typically used off-field either as a shielder or as a trigger for Burgeon reactions. Learn about Thoma’s best builds, Talent priority, best weapons, best artifacts, and best teams in this quick guide.

More extensive testing is in progress. Note that the information given is subject to change if and when new discoveries are made.

The full-length guide (currently in the process of being updated) is available here. Join our Discord to check on and participate in the theorycrafting process.

New Content

Rightful Reward	A Fontaine craftable weapon whose value to Burgeon and shielder playstyles depends heavily on the team being able to activate its passive.
Ballad of the Fjords	A Battle Pass weapon that Burgeon Thoma can use purely due to its passive. Generally not recommended unless you cannot craft Kitain Cross Spear.
Wriothesley	The newest Cryo DPS that can utilize Thoma’s shield in his Burnmelt teams.

Infographic

Design: euphorysm
Content: nova_licious

Design: euphorysm
Content: nova_licious

Character Overview

Playstyles

Burgeon

This is where Thoma shines as a damage dealer; Burgeon excels at dealing multi-target damage. Thoma’s ER requirements can be high in this playstyle because secondary Pyro units will interfere too often when setting up Burgeon and are, therefore, not recommended on Burgeon Thoma’s teams.

It is important to note that Burgeon is a Transformative Reaction: its damage only scales with Elemental Mastery and Thoma’s level.

Shield Support

Thoma provides a shield for his teammates and may buff them using support-oriented artifacts. His shield is fairly strong but requires an on-field character to use Normal Attacks in order to maintain it. His Burst’s Fiery Collapses may interfere with reactions in some teams.

Talents

Constellations

Burgeon Thoma

Level and Talent Priority

Level 90 > Skill = Burst 

It is extremely important to level Thoma to 90 in this playstyle, as that increases Burgeon damage by ~30% when compared to Level 80.

Burgeon Thoma’s Talent levels do not considerably increase his damage and can remain unleveled. However, leveling his Burst and Skill may increase survivability and resistance to interruption in the form of a stronger shield.His Normal Attacks can remain unleveled as playing Thoma on-field is not recommended.

Artifacts

ER Requirements

Solo Pyro, 2 Favonius teammates	One Skill	Two Skills
C0–C3, R3 Kitain	~240%	~210%
C4+, R3 Kitain	~190%	~165%

• Funneling a teammates’ Favonius proc to Thoma lowers ER requirements by 15–25%.
• Use the Energy Recharge Calculator to determine the exact requirements for your team and rotation.
• Thoma’s Burst is an integral part of dealing Burgeon damage as it is his main source of Pyro application— you should have enough ER to cast his Burst every rotation consistently. With Thoma’s high ER requirements, Kitain Cross Spear is an excellent option as it simultaneously lowers ER requirements with its passive and increases Burgeon damage with its EM secondary stat. Each refinement increases the amount of Energy given by Kitain’s passive so refinements are highly recommended.

Artifact Main Stats

Sands	Goblet	Circlet
EM / ER%	EM	EM
HP% / ER%	HP%	HP%

Substats: ER until requirement > EM 

HP% main stats can be used as necessary to allow Thoma to function as the sole defensive unit in the team, thus opening a slot for a more offensive teammate such as Childe or Fischl; Thoma still does decent Burgeon damage, and the team as a whole suffers a minimal DPS loss. Artifact set and weapon recommendations remain the same as those for a triple EM build.

Artifact Sets

4pc Flower of the Paradise Lost	Best-in-slot by a slight margin compared to 4pc Gilded. However, Gilded Dreams has a more Resin-efficient Domain.
4pc Gilded Dreams	One of Thoma’s best sets in a Burgeon playstyle. The set typically provides 230 EM with its 2pc and 4pc effect combined, as it is not recommended to have Pyro teammates in Burgeon teams.
2pc EM + 2pc EM	A useful placeholder until a 4pc set is obtained, as it provides 160 EM. It is also accessible, as 2pc Wanderer’s Troupe can be farmed passively.
2pc EM + 2pc ER%	2pc Emblem’s ER% helps fulfill Thoma’s ER requirements, while the other set still provides EM.
4pc Crimson Witch	4pc Crimson technically benefits Burgeon damage, but it is inferior to 4pc Gilded. Only use it if you already have a set on hand and don’t want to farm a new one.

It is recommended that a team member (typically the Dendro unit) equips 4pc Deepwood Memories as Burgeon damage benefits heavily from Dendro RES Shred.

Weapons

Kitain Cross Spear	Kitain reduces Thoma’s ER needs and provides him with EM. Refinements are recommended. When using Kitain, use Thoma’s Burst before his Skill.
Dragon’s Bane	Dragon’s Bane provides EM and slightly increases Talent damage; however, it does not assist with ER requirements.
Rightful Reward	Rightful Reward strengthens Burgeon Thoma’s shield through its HP secondary stat and can lower ER requirements through its passive’s Flat Energy. However, its passive is only useful if the team has healing. Calculations are still being done on this weapon so this weapon may be better or worse than the other options within this list. Even then, its ranking will depend on what healer (if any) you have on a team.
Favonius Lance	Favonius helps fulfill Thoma’s ER needs and reduces teamwide ER needs. However, it does not provide any EM.
Ballad of the Fjords	Fjords provides EM only with its passive. It becomes better at higher refinements but should only be used if other options are not available.

Teams

Burgeon

Thoma is paired with a Dendro character and a Hydro character, in order for Bloom to occur. Burgeon is then triggered on the Dendro Cores generated by Bloom with Thoma. A defensive unit must be included if Thoma does not have sufficient HP, as Burgeon damages on-field units. It is generally only recommended to run HP% main stats if the on-field unit also makes a significant contribution to team damage (e.g., Ayato and Childe).

Dendro Slot

Nahida	The best Burgeon support. Nahida applies a considerable amount of Dendro both as a driver and from off-field. Her Burst can usually be ignored, as its EM buff does not typically hold value to the on-field unit.
Baizhu	As a Burgeon support, Baizhu brings important aspects for survivability: shields and healing. As the sole Dendro unit in the team, Baizhu’s Dendro application can fall behind; however, using his Normal Attacks on-field can provide considerable single-target application.
Dendro Traveler	A great option. It is extremely important to transmute Dendro Traveler’s Burst with either Hydro or Electro, as the Pyro transmutation will stop Dendro application, and thus all Burgeon damage, prematurely.
Yaoyao	Yaoyao excels particularly with teams that lack a healer otherwise (for example, those with Childe or Ayato). However, her Dendro application from off-field is lackluster and she should be a secondary Dendro unit in most teams.
Kirara	Kirara is a good shielder for Burgeon teams; however, she should not be relied on as the sole Dendro applier from off-field. Additionally, using her on-field is problematic as she cannot use Normal Attacks to proc Hydro application via coordinated attacks.
Collei	Collei has relatively short cooldowns, but also a short duration on her Burst which forces shorter team rotations. This is particularly conflicting with Thoma as he has longer cooldowns and a long-lasting Burst. Because of this, Collei is only recommended as a second Dendro unit.
Kaveh	An interesting choice for Burgeon teams; Kaveh is able to mitigate Burgeon self-damage with his A1, but his Dendro Core detonation can sometimes steal Dendro Cores from Thoma — though this can be partially mitigated with timing. It is not recommended to use C6 Kaveh in this position, as he steals too many Dendro Cores from Thoma.
Alhaitham	Deals lower damage outside of his Spread teams. Alhaitham should not be run with a second Dendro unit to avoid triggering Burning. Fischl should be used as a Flex unit to add to Alhaitham’s personal damage without taking much from Thoma’s Burgeon. 4pc Deepwood can be equipped by a non-Dendro unit if running other sets increases Alhaitham’s damage.

Hydro Slot

Ayato	Ayato applies Hydro from both on- and off-field while also contributing to team damage. A top contender for allowing Thoma to use two Skills per rotation due to Ayato’s more flexible rotations.
Kokomi	Kokomi provides on-field and off-field Hydro application with immense healing, something often lacking in Burgeon Teams. However, Kokomi will want to Burst every rotation for Skill uptime as well as increasing her on-field damage, so her ER requirements in these teams may be higher.
Childe	Childe has excellent AoE Hydro application and damage while on-field in melee stance, but this application drops off outside of that stance. Best used with C2+ Thoma so he can Vaporize his Burst.
Xingqiu	Xingqiu provides excellent off-field Hydro application and gives damage reduction. However, Xingqiu’s application is single-target, which can conflict with Burgeon wanting to be used in AoE circumstances.
Yelan	Yelan is similar to Xingqiu, but can generally deal more personal damage and buff the on-field character’s damage.

Flex Slot

2nd Dendro	A second Dendro unit activates Dendro Resonance, buffing EM, and can increase Dendro Core production. Additionally, the unit can run 4pc Instructor to further increase the team’s EM. See Dendro teammates for more details.
Fischl	Provides excellent off-field single-target damage while creating Quicken and Electro-Charged auras that extend Dendro application. Oz targets Dendro Cores last, so she will not steal many Dendro Cores.
Albedo	A steady off-field damage dealer, but his Burst is often inconsequential, even though it provides the team with EM.
Cryo Units	Allow for compositions that extend Dendro application by applying Cryo (Freeze Bloom or Fridge). Additionally, the Frozen reaction results in crowd control. Freeze Bloom teams are usually recommended to have either Childe or Ayato as the Hydro unit.
Kazuha	An excellent grouping option for enemies and Dendro Cores alike. Can additionally buff an on-field Hydro character by Swirling Hydro.
Sucrose	Provides some grouping and an EM buff; however, Sucrose is usually used as an on-field unit and can decrease overall Dendro Core production.
2nd Hydro	This unit can be a healer if the team uses an on-field Hydro, or either Yelan or Xingqiu to reduce the Hydro unit’s ER requirements. The additional Hydro application is useful in capitalizing on high Dendro application (for example, in the case of an on-field Nahida). See Hydro characters for more details.

It is not recommended to have a Pyro unit in the flex slot.

Example Teams

This is not a comprehensive list of teams, and the inclusion of a certain team or lack thereof does not necessarily indicate the power level of the team in question. 

Shield Support Thoma

Talent Priority

Skill = Burst

Leveling Thoma’s Skill and Burst increases the strength of his shield. Thoma’s Normal Attacks can remain unleveled as playing him on-field is not recommended.

Artifacts

ER Requirements

Double Pyro	R3 Favonius Lance	R3 Kitain
C0–C3	~210%	~220%
C4+	~170%	~175%

Artifact Stats

Sands	Goblet	Circlet
ER / HP%	HP%	HP% or CRIT Rate (if using Favonius)

Substats: ER (until requirements are met) > HP% > CRIT Rate (if using Favonius) > Flat HP

Artifact Sets

4pc Noblesse Oblige	4pc Noblesse Oblige gives Thoma’s team a useful ATK% buff after using his Burst.
2pc HP% + 2pc Emblem of Severed Fate	2pc Emblem makes it easier to fulfill ER needs, while 2pc HP% strengthens Thoma’s shield.

Additionally, any combination of HP%, Emblem, and rainbow (pieces that don’t make a set bonus) artifacts may be used depending on ER requirements, as better substats may be more useful than set bonuses.

Weapons

Favonius Lance	Favonius as a useful ER% main stat. Its passive also reduces ER requirements teamwide. For consistent Favonius Lance passive procs, it’s recommended to build ~40% CRate at R3 and ~30% at R5. This number assumes 2–3 NAs are weaved in.
Kitain Cross Spear	Kitain has a wasted EM main stat but reduces Thoma’s ER requirements through its passive. Refinements are recommended. If using Kitain, cast Thoma’s Burst before his Skill.
Black Tassel	Black Tassel’s HP% main stat makes for a stronger shield, but it doesn’t help with ER requirements.
Rightful Reward	This Polearm also has an HP% main stat, alongside a passive that can possibly be useful by providing Energy. Due to many of Shield Support Thoma’s teams not having healers, the passive on this weapon is often wasted.

Teams

Team-Building

• It is recommended to use Thoma on a team with a character that uses on-field Normal Attacks to stack his shield.
• On some teams, Thoma’s Fiery Collapses may interfere with reactions.

Pyro DPS Support

Shield Support Thoma’s most popular use. He acts as a support for a Pyro on-field DPS (e.g., Yoimiya or Hu Tao) by providing a shield, Pyro Resonance, and often helping set up VV.

Notable Teammates

Below are the Pyro on-field DPS characters with whom Thoma has notable synergy. For an understanding of the supports used alongside these units, please refer to their respective guides.

Yoimiya	Thoma has great synergy with Yoimiya as he provides survivability and resistance to interruption (things Yoimiya needs) while she maintains his shield through her Normal Attacks.  Thoma’s Pressurized Collapses rarely interfere with reactions, due to Yoimiya’s range.
Hu Tao	Thoma provides a strong shield and resistance to interruption to Hu Tao. This is particularly useful, as she does not want healers in her teams. Thoma is also useful for setting up Viridescent Venerer RES Shred. Thoma may steal Vaporizes from Hu Tao if using a pre-C6 Xingqiu, but this is not an issue in Double Hydro compositions.

Example Teams

This is not a comprehensive list of teams, and the inclusion of a certain team or lack thereof does not necessarily indicate the power level of the team in question. 

General Shielder

Thoma can be generally useful as a shielder, as long as the on-field unit uses Normal Attacks.

Notable Teammates

Below are damage dealers who can use Thoma as a shielder. See their respective guides for detailed information on their teams.

Wriothesley	In Wriothesley’s Burnmelt teams, Thoma is an excellent shielder option. Thoma can also maintain Burning with his Fiery Collapses and, at C6, give a Normal and Charged Attack DMG Bonus.  Wriothesley requires stronger sustain from teammates due to his HP drain. Alongside Bennett, Thoma provides strong survivability — something particularly important for a C0 Wriothesley.
Wanderer	Thoma is one of Wanderer’s options for a shielder. When paired with Bennett, Thoma allows Wanderer to take advantage of Pyro Resonance, while also giving his Normal and Charged Attacks a DMG Bonus with C6.
Xiao	Xiao benefits from Thoma for similar reasons as Wanderer; however, it is essential to use NA cancels while plunging with Xiao in order to maintain Thoma’s shield.
Cyno	Thoma acts as a shielder in Cyno’s Quickburn and Chaos teams. Thoma’s shield is able to last through the entirety of Cyno’s Burst, which allows Cyno to take full advantage of Thoma’s interruption resistance and NA DMG Bonus at C6.
Itto	Another on-fielder that uses Normal Attacks and benefits from the interruption resistance provided by Thoma’s Shield.

Example Teams

This is not a comprehensive list of teams, and the inclusion of a certain team or lack thereof does not necessarily indicate the power level of the team in question. 

Credits

vazellea, jukoist, miannes, dorketh, raven9205, mystathi, cuzimori, grankrathalos, polomo

Team images courtesy of the KQM portrait generator.