Operator Module

Operator Modules, or simply Modules, are a feature in Arknights, introduced alongside class branches in Dossoles Holiday.

Only available for 4★ and above Operators, Modules are a special item that acts as an "equipment" which improves their attributes and either upgrades their trait or adding a new trait when equipped, improving the Operator's performance particularly in their primary roles. All Modules (except the default Badges) are unique to each Operator and cannot be equipped by the others, even those in the same class, branch, or rarity.

Modules are initially not available and must be unlocked by using Module Data Block, upgrade materials, and LMD once the player completes certain tasks termed Module Missions and by raising the corresponding Operator's promotion, level, and Trust to a specific threshold.

Since the Lingering Echoes update, Modules can be upgraded through two additional stages to improve the corresponding Operator's talent or add a new talent, and enhance its attribute improvements at the cost of more Module Data Blocks, upgrade materials, and LMDs, as well as a large amount of Data Supplement Stick for the second stage and Data Supplement Instrument for the third stage.

List

The following is a list of class branches with available Modules including their effects and which Operators have them as of July 9, 2024, sorted alphabetically by their branch name and introduction date.

Branch	Module	Description
Chain Caster	CHA-X	Reduces the damage loss in each jump to 10% and increases the Slow duration of each hit to 0.8 seconds (the same as Decel Binder Supporters). Introduced in: Near Light
	CHA-Y	Removes the damage loss in each jump. Introduced in: Near Light
Splash Caster	SPC-X	Extends the Splash Caster's attack range to 3×3 tiles with a 1-tile extension up front. Introduced in: Guide Ahead
	SPC-Y	Reduces the Splash Caster's DP cost by 8. Introduced in: Guide Ahead
Mystic Caster	MSC-X	The Mystic Caster can store one additional attack. Introduced in: Lingering Echoes
	MSC-Y	When the Mystic Caster stores at least one attack, their ASPD is increased by 30. Introduced in: An Obscure Wanderer
	MSC-Δ	When the Mystic Caster deals Arts damage, the target will also be inflicted with Necrosis Damage equal to 8% of the damage dealt. Introduced in: Episode 13: The Whirlpool that is Passion
Core Caster	CCR-X	The Core Caster's attacks ignore 10 RES. Introduced in: Where Vernal Winds Will Never Blow
	CCR-Y	The Core Caster restores 1 SP when attacking elite or boss enemies. Introduced in: Where Vernal Winds Will Never Blow
	CCR-Δ	When the Core Caster deals Arts damage, the target will also be inflicted with Necrosis Damage equal to 8% of the damage dealt. Introduced in: [CN] 5th Anniversary Celebration
Blast Caster	BLA-X	The Blast Caster's ATK is increased when attacking targets further away from their position, which caps at 10%. Introduced in: A Flurry to the Flame
	BLA-Δ	When the Blast Caster deals Arts damage, the target will also be inflicted with Burn Damage equal to 8% of the damage dealt. Introduced in: [CN] Path of Life
Phalanx Caster	PLX-X	The DEF and RES buff while the skill is not active is increased to 215% and 25, respectively. When the Phalanx Caster's skill is active, their DEF and RES are increased by 100 and 10, respectively. Introduced in: Episode 12: All Quiet Under the Thunder
	PLX-Y	The Phalanx Caster deals more damage as more enemies as within their range, which caps at 15%. Introduced in: The Rides to Lake Silberneherze
Mech-Accord Caster	FUN-X	The Drone's initial damage is increased to 35% of the Mech-Accord Caster's ATK. Introduced in: The Rides to Lake Silberneherze
	FUN-Y	The Drone's damage cap is increased to 120% of the Mech-Accord Caster's ATK. Introduced in: The Rides to Lake Silberneherze

Branch	Module	Description
Duelist Defender	HES-X	The Duelist Defender's SP recovery/restoration rate is reduced by 80% while they are not blocking enemies. Introduced in: Stultifera Navis
	HES-Y	The Duelist Defender can now restore SP while not blocking enemies. When the Duelist is blocking enemies, their ATK and DEF are increased by 15%. Introduced in: An Obscure Wanderer
Guardian Defender	GUA-X	When the Guardian Defender heals friendly units whose HP had fallen below 50%, the healing amount is increased by 15%. Introduced in: Lingering Echoes
	GUA-Y	The Guardian Defender takes 15% less damage. Introduced in: Lingering Echoes
Protector Defender	PRO-X	When the Protector Defender is blocking enemies, their DEF is increased by 20%. Introduced in: An Obscure Wanderer
	PRO-Y	The Protector Defender can block four enemies on their own. Introduced in: An Obscure Wanderer
Fortress Defender	FOR-X	When the Fortress Defender attacks blocked enemies, their ATK is increased to 110%. Introduced in: Episode 13: The Whirlpool that is Passion
Juggernaut Defender	UNY-X	The Juggernaut Defender takes 15% less damage from enemies they are blocking. Introduced in: Zwillingstürme im Herbst
	UNY-Y	The Juggernaut Defender's ATK and DEF is increased by 8% when there are no allies in the surrounding eight tiles. Introduced in: [CN] Path of Life
Sentinel Protector Defender	SPT-X	Reveals invisible enemies within the Sentinel Protector Defender's attack range. Introduced in: [CN] Operation Lucent Arrowhead

Branch	Module	Description
Instructor Guard	INS-X	The damage dealt by the Instructor Guard when attacking enemies they are not blocking is further increased to 130%. Introduced in: Dossoles Holiday
	INS-Y	The Instructor Guard can now be deployed in both melee and ranged tiles. Introduced in: Dossoles Holiday
Swordmaster Guard	SWO-X	The Swordmaster Guard's skills deal 10% more damage. Introduced in: Break the Ice
	SWO-Y	The Swordmaster Guard's attacks ignore 70 DEF. Introduced in: Break the Ice
Dreadnought Guard	DRE-X	When the Dreadnought Guard attack enemies that are being blocked, their ATK is increased to 115%. Introduced in: Invitation to Wine
	DRE-Y	When the Dreadnought Guard's HP is reduced to 0, they will survive with their HP fully restored and ASPD increased by 30, but their maximum HP is reduced by 60%. This effect can only be triggered once per deployment. Introduced in: Invitation to Wine
Musha Guard	MUS-X	When the Musha Guard's HP falls below 50%, they receive a 25% Sanctuary. Introduced in: What the Firelight Casts
	MUS-Y	When the Musha Guard's HP is reduced to 0, they will survive with 30% HP. This effect can only be triggered once per deployment. Introduced in: The Black Forest Wills A Dream
Reaper Guard	REA-X	The HP restoration per hit in each attack is increased to 60. Introduced in: [Global] Hortus de Escapismo, [CN] So Long, Adele
Centurion Guard	CEN-X	When the Centurion Guard attacks blocked enemies, their ATK increases to 110%. Introduced in: So Long, Adele
	CEN-Y	When the Centurion Guard's HP is above 50%, the Physical damage they take is reduced by 20%. Introduced in: So Long, Adele
Fighter Guard	FGT-X	The Fighter Guard can dodge Physical attacks 15% of the time. Introduced in: [CN] Here a People Sows
	FGT-Y	The Fighter Guard has their ASPD increased by 10 so long as their HP is above 50%. Introduced in: [CN] Here a People Sows
Lord Guard	LOR-X	The Lord Guard's attacks deal an additional instance of Arts damage equal to 10% of their ATK. Introduced in: [CN] 5th Anniversary Celebration
	LOR-Y	If there are at least 2 enemies within the Lord Guard's attack range, their ASPD is increased by 12. Introduced in: [CN] 5th Anniversary Celebration

Branch	Module	Description
Multi-target Medic	RIN-X	The Multi-target Medic's range is extended to an adjusted 3×4 tiles with a 1-tile extension up front. Introduced in: Episode 9: Stormwatch
	RIN-Y	The Multi-target Medic can now heal up to four friendly units at once. Introduced in: Episode 9: Stormwatch
Therapist Medic	WAH-X	The Therapist Medic has Status Resistance and Negative Taunt. Introduced in: Stultifera Navis
	WAH-Y	Removes the healing penalty on further targets. Introduced in: Stultifera Navis
Medic Medic	PHY-X	When the Medical Medic heals friendly units whose HP had fallen below 50%, the healing amount is increased by 15%. Introduced in: [Global] Il Siracusano, [CN] Episode 11 Warm-Up
	PHY-Y	When the Medical Medic heals friendly units on melee tiles, the healing amount is increased by 15%. Introduced in: [Global] Il Siracusano, [CN] Episode 11 Warm-Up
Incantation Medic	INC-X	The healing amount on each attack is increased to 60%. Introduced in: The Rides to Lake Silberneherze

Branch	Module	Description
Deadeye Sniper	DEA-X	The Deadeye Sniper's ATK is increased when attacking targets further away from their position, which caps at 15%. Introduced in: Episode 9: Stormwatch
	DEA-Y	The Deadeye Sniper restores 1 SP in each attack so long as the target is not defeated/destroyed (i.e. if the attack would defeat/destroy the target, no SP will be restored). Introduced in: Episode 9: Stormwatch
Artilleryman Sniper	ART-X	When the Artilleryman Sniper attack blocked enemies, their ATK is increased to 110%. Introduced in: Guide Ahead
	ART-Y	The Artilleryman Sniper's attacks ignore 100 DEF. Introduced in: Guide Ahead
Heavyshooter Sniper	ARC-X	Reduces the Heavyshooter Sniper's redeployment time by 25 seconds. Introduced in: Episode 10: Shatterpoint
	ARC-Y	When the Heavyshooter Sniper attack enemies right in front of them, their ATK is increased to 105% and the attack will never proc the target's Physical Dodge. Introduced in: Ideal City
Marksman Sniper	MAR-X	When the Marksman Sniper attack aerial enemies, their ATK is increased to 110%. Introduced in: Dorothy's Vision
	MAR-Y	If there are ground enemies within the Marksman Sniper's attack range, their ASPD is increased by 8. Introduced in: Dorothy's Vision
Besieger Sniper	SIE-X	When the Besieger Sniper attack enemies with a weight of at least 3, their ATK is increased to 115%. Introduced in: What the Firelight Casts
Flinger Sniper	BOM-X	The Flinger Sniper's attacks now releases a second shockwave. Introduced in: Lone Trail
Hunter Sniper	HUN-X	When the Hunter Sniper's ammo is depleted, they will load one additional ammo in the next reload. Introduced in: [CN] Path of Life
Spreadshooter Sniper	RPR-X	The Spreadshooter Sniper deals 160% damage when attacking enemies right in front of them. Introduced in: [CN] A Kazdelian Rescue

Branch	Module	Description
Executor Specialist	EXE-X	When the Executor Specialist is retreated, 80% of their current DP cost is refunded. Introduced in: Near Light
	EXE-Y	If there are no friendly units in the adjacent tiles to the Executor Specialist, their ATK is increased by 10%. Introduced in: Near Light
Merchant Specialist	MER-X	Reduces the DP drained by the Merchant Specialist when they are deployed to 2 DP every 3 seconds (also reduces the minimum DP threshold to automatically retreat the Merchant Specialist when there are insufficient DP to 1). Introduced in: Invitation to Wine
	MER-Y	The Merchant Specialist's ATK is increased by 4% whenever their trait drains DP, which stacks up to 5 times. Introduced in: The Rides to Lake Silberneherze
Dollkeeper Specialist	PUM-X	The Substitute has +15% ATK. Introduced in: Stultifera Navis
	PUM-Y	The Substitute has +15% HP. Introduced in: Stultifera Navis
Ambusher Specialist	AMB-X	Reduces the speed of enemies within the Ambusher Specialist's range by 20%. Introduced in: Ideal City
	AMB-Y	Increases the Ambusher Specialist's innate Physical/Arts dodge rate to 65%. Introduced in: What the Firelight Casts
Hookmaster Specialist	HOK-X	Enemies being dragged by the Hookmaster Specialist receive Arts damage based on how far they are dragged (see Debuff#Distance-based damage for more information). Introduced in: Ideal City
	HOK-Y	When the Hookmaster Specialist shifts a distant enemy, the shift level is increased by 1. Introduced in: [CN] Path of Life
Push Stroker Specialist	PUS-X	When the Push Stroker Specialist is deployed on ranged tiles, half of their base DP cost are refunded. Introduced in: A Flurry to the Flame
	PUS-Y	When the Push Stroker Specialist is blocking at least two enemies, the shift force they deliver is increased by 1. Introduced in: A Flurry to the Flame
Trapmaster Specialist	TRP-Y	There is a 20% chance that the trap deployed by the Trapmaster Specialist does double damage when triggered. Introduced in: Episode 12: All Quiet Under the Thunder
	TRP-Δ	The Trapmaster Specialist and their traps can now be deployed on both melee and ranged tiles. Introduced in: [CN] Operation Lucent Arrowhead
Geek Specialist	GEE-X	When the Geek Specialist's HP is above 80%, their automatic SP recovery rate is increased by 0.25/second. Introduced in: Hortus de Escapismo

Branch	Module	Description
Summoner Supporter	SUM-X	The first of the Summoner Supporter's summoned unit that are deployed will not be counted towards the Unit Limit. Introduced in: Dossoles Holiday
	SUM-Y	Increases the deployment count of the Summoner Supporter's summoned unit by 3 and reduces their DP cost (varies with the summon). Introduced in: Dossoles Holiday
Decel Binder Supporter	DEC-X	If an enemy is inside the Decel Binder Supporter's range, their automatic SP recovery rate is increased by 0.2/sec. Introduced in: Episode 10: Shatterpoint
	DEC-Y	Extends the Slow duration of the Decel Binder Supporter's attacks to 1.2 seconds. Introduced in: Episode 10: Shatterpoint
Hexer Supporter	UMD-X	The Hexer Supporter's attacks inflict 10% Enfeeble (reducing the target's ATK) for 2 seconds. Introduced in: Lone Trail
Artificer Supporter	CRA-X	Increases the deployment count of the Artificer Supporter's Support Devices by 1 and reduces their DP cost (varies with the Device) Introduced in: Hortus de Escapismo
Abjurer Supporter	BLS-X	The Abjurer Supporter now heals friendly units without penalty while their skill is active. Introduced in: Come Catastrophes or Wakes of Vultures

Branch	Module	Description
Charger Vanguard	CHG-X	Increases the DP generated when the Charger Vanguard defeats an enemy to 2. Instead of the base DP cost, their current DP cost will be refunded when the Charger Vanguard is retreated. Introduced in: Break the Ice
	CHG-Y	When the Charger Vanguard attack enemies whose HP had fallen below 40%, their ATK is increased to 115%. Introduced in: Break the Ice
Pioneer Vanguard	SOL-X	When the Pioneer Vanguard is blocking enemies, their ATK and DEF are increased by 8%. Introduced in: Il Siracusano
	SOL-Y	Reduces the Pioneer Vanguard's DP cost by 4 at their first deployment. Introduced in: Il Siracusano
Standard Bearer Vanguard	BEA-X	The Operator in front of the Standard Bearer Vanguard has their block count increased by 1 when their skill is active. Introduced in: The Black Forest Wills A Dream
Tactician Vanguard	TAC-X	The Reinforcement takes 15% less damage from enemies it were blocking. Introduced in: [CN] Babel
	TAC-Y	Enemies blocked by the Reinforcement Taunts friendly units, and the damage dealt by the Tactician against them is increased to 165%. Introduced in: [CN] Babel