Arknights: Azure's Module Upgrade Tier List

The Module Upgrade system is a new mechanic that will be introduced during the Lingering Echoes event that allows players to upgrade any available Module they already have to Stages 2 and 3, further improving the stat boosts and modifying the Operator's Talents. This system is designed to provide Operators with much better tailored boosts, instead of the more generic Trait changes so far, and can result in incredible boosts in viability depending on the Module.

The materials necessary for these upgrades are Data Supplement Strips for Stage 2 and Data Supplement Devices for Stage 3. These two new materials will be introduced alongside the Stationary Security Service mode, a permanent event that provides these materials in very limited amounts. Other than this new gamemode, these materials are pursachable in certain event stores.

Due to the scarcity of these new materials (each 6★ Operator requires 60 and 20 of each respectively,  plus more Module Data Blocks) and the high regular material cost of these upgrades (7 Tier 5 Materials and 220k LMD total from Stage 1 to Stage 3), it is incredibly important to be able to prioritize which Module Upgrades to focus on and to discern between which ones are not worth the hassle, which ones are, and up to which Upgrade Level.

This tier list will focus on the relative strength of the Module Upgrade exclusively. This will not rate the overall viability of the Operators post-module, but instead how strong these Module Upgrades are and how much they boost the Operator's performance individually. In short, if you already use these Operators often, how prioritary are their Module Upgrades?

(List updated up to An Obscure Wanderer)

These Module Upgrades are incredibly powerful and fundamentally change how the Operator plays or massively improves their combat performance. Operators in this tier will feel significantly more powerful with their Module Upgrades, even going from Stage 2 to 3. Operators with Module Upgrades whose boosted Talents are multiplied by a Skill are very likely to end up here, as the effect will be boosted multiple times.

Effect: Slows the movement speed of enemies within this unit's attack range by 30% and of enemies outside this unit's attack range by 18% (unaffected by Skill).

This upgrade doubles the regular values of Mostima's Talent and adds an additional bonus to further slow down enemies outside of range. This Talent interacts with Skill 3, tripling the Movement Speed reduction to 90% (99% with P5) in a very large area, slowing all enemies down to a crawl.

Effect: When deployed, grant 1 [Offensive/Defensive-Recovery SP] to all allies every 3 seconds. Ch'en grants herself 1 additional SP.

This upgrade boosts Ch'en's ability to support other Operators with the adequate SP recovery type further, but most importantly it significantly improves Ch'en's skill uptime, addressing one of the biggest issues she has.

Effect: Self redeployment time -30 seconds.

Simple as it may seem, this upgrade massively enhances the performance of Skadi's Skill 2, giving her great helidrop capabilities and an skill uptime of over 75% (without Potentials). Thanks to this upgrade, Skadi will be able to exert pressure all over the map and take down elite enemies from almost anywhere.

Effect: When in the team, All [Abyssal Hunters] Operators gain ATK +22% and Max HP +20%.

If the previous Module Upgrade was focused on improving the value of Skadi's second Skill, this one does the same for her Skill 3. Since this upgrade affects herself as well, Skadi will receive an insane boost to survivability to be able to stay on the field for much, much longer while constantly shrugging off Arts attacks. It also massively boosts the performance of all other Abyssal Hunters, turning them into really tanky Operators with monstruous HP. Finally, this also stacks with other Abyssal Hunter upgrades, which we will see soon.

It is important to not, though, that while this upgrade is very powerful on its own, it is severely overshadowed by the [X] Module. Even during Abyssal Hunter clears, the former will be preferred to turn Skadi into an actually competent Operator on her own. While this Upgrade its quite powerful in a vaccuum, keep in mind that Skadi's [X] Module is even more important for her.

Effect: [Substitute] inflicts -60% movement speed to nearby enemies and deals 80% Arts damage to them every second, and gains 15 additional SP upon swapping back to the original.

Specter the Unchained is perhaps the main reason why Module Upgrades even exist, as she was considered an often worse alternative to her regular version due to her SP charging issues. This Module solves that with a rather large SP boost upon swapping back to her original version on top of dealing twice the Arts damage compared to Stage 1 and with 20% extra slowing abilities. This Module Upgrade has it all!

Effect: When in squad, all [Abyssal Hunters] Operators gain +30% Max HP, and SP recovery speed +0.5 SP/sec (only the highest effect of this type will be applied).

Much like Skadi's Module Y, Specter the Unchained's focuses on providing incredibly strong buffs to her fellow Abyssal Hunters. The HP boost is simply massive (especially when paired with other team effects), and the SP recovery makes their already rather quick skill positively spammable. This skill provides a worse overall skill uptime for Specter the Unchained, but not by a lot.

Effect: When deployed, all [Abyssal Hunters] operators recover 3.5% Max HP every second and receive 30% less Physical and Arts damage from all enemies.

Yet another massive boost to all Abyssal Hunters. This one simply makes them completely immortal.

Jokes aside, Damage Reduction is an incredibly rare effect and for a good reason. Paired with this incredibly strong regen (and possibly even over 50% extra HP from Skadi and Specter the Unchained) Gladiia and all her fellow hunters will be able to withstand and even outheal most enemies in the game with no outside healing source. With all these boosts, Andreana is capable of tanking Patriot's spears and regenerating to full HP before he fires another one!

Effects: When there are no enemies in the 4 adjacent tiles, ATK +10%, increase SP recovery rate by 0.25 SP/sec.

One of Passenger's biggest issues is that his Skill 3 charge time is quite atrocious, which really hurts his overall DPS. This Module Upgrade variant seeks to fix that, giving him a better uptime so he can call down thunder and lightning upon his enemies more often.

Effect: When attacking enemies with 70% or more HP, increases Passenger's damage dealt to them by 28% for 4 seconds.

If instead what you want is higher burst damage, this option will greatly improve that aspect of Passenger's kit, letting him take advantage of the charges his Skill 3 can hold for maximum DPS over the 4 second duration of this boost.

Effect: When deployed, this unit gains 9 SP and 1 Shield. Restores 7 SP after the Shield breaks

While this may not seem that incredible, 9 starting SP means Archetto will be able to cast her Skill 2 immediately upon deployment, and her Skill 3 in 6 seconds (or as soon as her Shield pops!). This greatly boosts Archetto's capabilities as an opener for most maps.

Effect: When attacking or using skills, 50% chance to increase ATK by +60%.

Usually Module Upgrades with this sort of effect barely increase the crit chance of each attack by ~5%, but Meteorite's boosts her own by a whopping 20%, which will be quite meaningful for her high-damage Skills.

Effect: Self redeployment time -28 seconds, deployment cost -2.

While this effect does not massively boost April's DPS, a redeployment timer and original DP cost decrease is practically everything she could ask for. Due to her redeploy-heavy playstyle, these benefits give more and more mileage as the stages go on, saving up a ton of DP and letting April control the battlefield much more freely.

Effect: When attacking, 28% chance to ignore the target's DEF

As little as an 8% boost looks on paper, Franka is one of those Operators whose main Skill actively interacts with their talent. In her case, a mere 8% on her base Talent transforms into a 20% extra chance to ignore Defense through her Skill 2, which is her main niche. This Module Upgrade makes Franka significantly more reliable.

Effect: When attacking, has a 28% chance to Bind the target for 3.5 seconds.

As with the previous Operator, Ethan's Module Upgrade is boosted by his Skill 2 quite significantly, resulting in an 84% chance to bind per attack compared to his former 75%. Not only that, but the duration extension also means he is now able to permanently keep enemies bound without the need of any Attack Speed boost at all, which makes Ethan one of the biggest winners where Module Upgrades are concerned.

Effect: When attacking, 25% chance to Bind the target for 4 seconds. Will not target Bound enemies

Once more, the strength of Indigo's Module Upgrades come from how her Skill 2 interacts with the Talent it modifies. In this case, her Bind chances are multiplied by 3 when her Skill is active for a 75% chance to bind. This, however, applies independently to all projectiles, and with no external modifiers Indigo is able to hold 2 extra charges (3 attacks at once) every time her target is bound. This results in a whopping 98.5% chance of chaining another Bind, or 99.3% with P5.

Effect: Normal attacks a have 33% chance to recover 1 additional SP.

Extremely simple, but this small boost of 13% is enough to massively propel Cutter's skill uptime, letting her use her skill much more often.

Effect: Healing from skills increases to 120%

Despite already having a great HPS on her Skill 2, this new Talent will her Purestream be able to utilize her first one even better thanks to the massive burst of healing it will be able to provide. Even if you want to continue using her Skill 2, the extra HPS is really nothing to scoff at!

These Operators have Module Upgrades that are as powerful as (if not more than) the ones in the previous tier, but hit their big breakpoint at Stage 2 and don't get as much of a boost from Stage 3 to immediately deserve it. Operators in this tier will perform perfectly fine with their Stage 2 Module, and won't miss much if you don't go all the way to Stage 3.

Effect: When healing an ally, grant 2 SP to the target.

Simple but very effective boost. With many squads completely replacing regular Medics in favor of Saria, this boost in her SP-boosting capabilities will enhance her support capabilities even further. Additionally, her Skill 3 will become a veritable SP battery, granting 2 SP per second to all viable targets.

Effect: Can use 5 summons (can only deploy 4 together). Summon functionality changes depending on selected skill.

Being able to deploy an additional summon is extremely powerful for Magallan, as it will give her much, much better control over the battlefield with either of her Skills. This Module Upgrade branch will make it much easier for her to solo stages if need be.

Effect: Can use 5 summons (can only deploy 4 together). Summon functionality changes depending on selected skill.

While the effect of Ling's Module Upgrade is the exact same as Magallan's [Y] Module Upgrades, the former takes much more advantage of its practical effects due to her Skill 3 fusion mechanics. Being able to deploy one extra summon means having a grand total of 3 higher-form Thunderers and 1 small one, which really is overkill for Ling.

Effect: After deployment, immediately gains 3 Shield. When a layer of Shield breaks, ATK +5% DEF +5% and recover 2 SP.

This effect will very quickly boost Nian's Attack and Defense to 15% permanently, making it quite a large stat boost for essentially no setup. With all three stacks of this buff, Nian will very easily surpass 900 Defense without any of her skills active. It's worth noting that the Stage 3 effect is also nothing to scoff at, granting her a total of 6% extra Attack and Defense and 3 SP per Shield layer broken.

Effect: When attacking, deal additional Arts damage equal to 55% Attack to the target the two targets with the lowest HP.

Since all of Mizuki's Skill interact with and rely on this Talent, this boost is a no-brainer to get. It will help Mizuki deal with large crowds of enemies even better by constantly utilizing his Arts capabilities and spreading status ailments all over. The Stage 3 upgrade further boosts the Arts hit by another 5%, so it might be worth considering if you use his Skill 1 very often.

Effect: Stunned enemies in W's range take +21% physical damage, gains 1 SP after killing an enemy.

While the additional damage effect is nothing to write home about, gaining SP after triggering her Skills really helps W perform much better. All of her better Skills work on a delay, and Skill 3 particularly is great burst DPS that scales really well against larger waves of enemies, so she is bound to get a ton of mileage out of the SP booster if she has a good position.

Effect: ATK +6%, Max HP +10%. When deployed, grant the same effect to two random allies.

Tired of constantly boosting Myrtle through Exusiai's Talent? Fret not! Now you can boost Elysium as well!

All jokes aside, a permanent +6% boost to Attack is pretty nifty, and assigning a second ally the buff at least gives you a bit more control over who gets at least one of them.

Effect: Can use a stronger "Typewriter" that lasts for a certain duration. The "Typewriter" has the same skill as Pozyomka and an independent Redeployment Time. "Typewriter": ATK +50 (total).

50 Attack may not seem like that much, but it is important to remember what makes Pozyomka so incredibly strong. The Typewriter has very similar qualities as a deployable as Weedy's Cannon, with the important difference of providing incredibly strong DPS anywhere on the stage without worrying about getting attacked. 50 Attack may seem small elsewhere, but it is quite powerful for something as oppressive as the Typewriter.

Effect: Increases Max HP by 60 after an enemy is defeated in the 4 surrounding tiles, stacking up to 30 times.

The second part of this Module Effect boost means Flamebringer will no longer have to defend a lane by himself for half an hour to avoid any killsteals. This will help him get the full HP stacks much, much more easily. If you are willing to go the extra mile, the Stage 3 Module gives him an extra 300 HP through this Talent.

Effect: When attacking unblocked enemies, deal 123% damage and gain 1 SP.

This effect is extremely similar to the Hand of Spreading relic from Crimson Solitaire. It will give Leizi one additional SP per enemy hit, even if it's through the bounces of her Trait, greatly boosting her uptime if enemies start to pile up.

Effect: Attacks inflict 0.8 seconds of Slow.

Though it may not seem like much, this boost allows Greyy to maintain a 100% Slow uptime with his Skill 2, aiding in his crowd control mechanics. 

The Module Upgrades in this tier are still strong enough to consider purchasing Stages 2 or 3, but they are not as impactful as the ones in the previous tiers. These upgrades may enhance the overall performance of the Operators in a somewhat noticeable way or open up new niches for them to perform, but they should not be considered prioritary over the ones in higher tiers.

Eunectes and Pallas are tiered by their [X] Module Upgrades here.

Every other Module Upgrade branch not featured in this list is likely not worth getting due to a mixture of their massive cost and low impact on their Operator. Module Upgrades in this tier often consist of small Attack, Attack Speed or Crit Chance boosts that result in negligible DPS gains (~100 for most Operators). Other Module Upgrades that belong here may expand on niches that don't benefit the Operator noticeably, such as Blemishine, Cliffheart or Breeze.

Keep in mind that none of these Module Upgrades are actively detrimental to the Operator, so the only reason they are here is the extreme cost and exclusivity of Module Upgrades, which will force players to decide which ones to get and which to ignore.

This Tier List has been updated up to An Obscure Wanderer.