M4A1

Overview

M4A1 Mod is a contender for "Strongest T-Doll Mod" in the game for numerous reasons: a strong AR that buffs ARs, strong tiles that get even stronger, a strong SPEQ that buffs the right stats for her (Damage and Armor, and RoF post SPEQ rework), a Skill 2 that opens up exodias and farming teams previously impossible to make, a Skill 2 that makes AR-15 Mod, an already strong Mod, even stronger. Her only minor downsides are her janky interaction with SOPMOD II Mod and the relatively expensive cost of Modding 3 her, and even then her Mod 3 is very worth it, due to how easy it makes farming with minimal repair costs (like farming P22 on Faith of Blood II EX in Isomer).

Getting M4A1 Mod 3 is the closest thing to "can't go wrong" in all of Girls' Frontline. Getting her to Mod 2 is absolutely recommended as soon as Commanders unlock Neural Upgrades, while her Mod 3 can wait until Commanders have a few other units modded (usually SOPMOD II and ST AR-15).

Strengths

OP Skill 2 - Exodia potential

Her Skill 2 opens up a variety of farming compositions and exodias previously impossible to make, and one of the main reasons is because of her 600% damage buff. The AoE splash is also beneficial, and so it's recommended to field a PEQ over a VFL on night missions.
Because of it's huge Damage buff, at the cost of RoF, it enabled building Double Jupiters and M4xodias, where HGs buff M4 (and her partner, usually IWS2000, on Double Jupiter) before 2 of them are retreated so M4 can trigger the cannon aspect (increase 600% Damage while reducing 70% RoF) of her Skill.

For more details, check this in-depth guide on how to use M4A1 Mod.

OP Skill 2 - Cheap farming teams

M4A1 Mod 3 enables cheap farming compositions that either required more dolls to achieve the same farming ability or presents a much lower cost in repairs and/or resources spent on farming teams because of her SPEQ that has +15 Armor. For example, when 10-4E farm was the best way to acquire cores, M4A1 Mod 3 was the only other way to farm it if Commanders did not have a duplicate of Carcano M91/38.

Another example is that M4A1 Mod 3 + shield HG (P22 or HS2000) is the most efficient way to farm p22 in Faith of Blood II EX, a map in Isomer, which presents a much higher yield of P22s, and cores, than its Normal map counterpart.

OP Skill 2 - Skill 2 interaction with ST AT-15

M4's Skill 2 interaction with ST AR-15 Mod's Skill 2 gives her an additional 20% damage buff which is a helpful buff when they're paired together.

Very strong AR buffing tiles

M4A1's strong AR buffing tiles gets even stronger with her Mod, buffing a whopping 32% Crit Rate and 20%, capable of guaranteeing 90% Crit Rate for ARs equipped with VFL, and max Crit Rate for the rare ARs that have a base Crit Rate of 30%, instead of the usual 20%.

Mod SPEQ

M4's SPEQ buffs her +15 Armor, which is what lets her tank damage on cheap farms, and +5 Damage, which fixes her somewhat low Damage stat. Post-chip arrival, it is buffed to a whopping +20 RoF and +20 Damage, not only making it worth more than AR chips, but making her Mod 3 even more worth it.

Weaknesses

Farming needs Mod 3

Her SPEQ gives M4A1 15 Armor, which is what enables her to farm cheaply, as she acts both as a tank and as a DPS. The issue with that is that it requires Modding 3 her, which is expensive, as she is a 4 to 5 star Mod and also requires enhancing her SPEQ to the max.

Janky L2D

M4A1 Mod's L2D is one of the earliest in the game, and so fell on the coinflip side of "it's very janky animated".

Janky Skill 2 with M4 SOPMOD II Mod

While on paper M4 Mod's Skill 2's interaction with SOP's Skill 2 sounds nice, in practice it ends up capping SOPMOD's cluster grenades to only affecting enemies marked by Seal of the Avenger, instead of affecting all enemy units.

Full Analysis

M4A1 is the first story AR received for free by clearing chapter 2 stage 6, but don’t take that to mean she’s anywhere close to subpar. Toting unique formation buffs, an  excellent self-buffing skill, and a well-rounded statline, M4A1’s versatility makes her a common choice for many Echelons.

M4A1 provides other ARs in the Echelon with 18% Damage and 30% Crit Rate via her buff tiles. Assuming these ARs are equipped with five-star VFL Crit Scopes, M4A1 will push them to 88% Crit Rate, which is as good as AR Crit Rate gets. While another Crit buffer can be employed, this is not recommended as it would break the cap by 8%, causing inefficiencies.

Really, the only downside to these buffs is that M4A1 does not apply them to herself. Because of this, an SMG such as UMP45 which buffs Crit Rate for the entire AR column could still top M4A1 in buff efficiency. It should be noted, however, that this can be offset by running more damage-oriented Echelon compositions. This can be done by making use of HGs that can buff every team member when placed on Tile 5 and Offtank SMGs that will make use of the additional buffs provided.

Moving onto her performance as an AR, M4A1’s skill is Damage Focus T, which boasts a 4 second Initial Cooldown, a 10 second duration, and a 70% damage boost effect. Her short Initial Cooldown makes her an excellent fit for ‘quick burst’ Echelon compositions, while her 10 second skill duration means that she will likely be boosted for the majority of many fights. Her 16 Second cooldown, however, can be problematic when one is facing prolonged fights where M4A1 sees her skill run out.

M4A1’s statline is also quite well balanced. She has 46 Damage, which is 1 less than her comparable Gr G36. 48 Accuracy allows M4A1 to hit most targets, though since ARs are naturally accurate this stat does not really speak to her strength. It is her 79 RoF which is arguably M4A1’s best quality. This stat allows her to possess considerable damage output compared to many other ARs.

In summary, M4A1 possesses all the tools she needs to out damage her competitors while also buffing her fellow ARs’ damage with her tiles. It is this incredible utility that makes M4A1 a great T-Doll to use at any point of the game, and for this reason, it is strongly recommended to level her up as soon as possible.

Team Options

ST AR-15

M4 SOPMOD II

M950A

P22

HS2000

ST AR-15 MOD

M4A1 Mod has numerous uses, ranging from continuing working as an AR buffer on a standard ARSMG to being a key on cheap farming compositions. Thus, her partners vary wildly depending on how she is being used:

• In standard ARSMGs, she can be paired with AR-15 Mod, 416 Mod, G36 Mod, among us other ARs. Do note that she's best not paired with SOPMOD II MOD, as, due to coding shenanigans, M4's Skill 2 hinders SOP's Skill 2 (as in it can make the secondary nades disappear).
• In cheap farming compositions, her partners usually are P22, HS2000, to give her shield and thus minimize damage is taken, or Calico, to buff how many shots she can get with her cannon.

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