There are lots of Mass Effect 2 weapons to choose from as you make your way through this space adventure sequel, so it can feel somewhat daunting to decide on which firearms you want to equip. This is made all the more tougher with the Mass Effect Legendary Edition, as you also have all of the DLC and special edition weapons included to bolster your selection further.
The question of what are the best Mass Effect 2 weapons doesn't have a definitive answer, as which guns work best for you will depend largely on the class you choose for Shepard and your individual playstyle – do you prefer to run and gun up close to your enemies, or keep to cover and shoot them from a distance? For that reason, we've got details in this guide for all of the Mass Effect 2 weapons, so you know where to obtain them from and can decide which will be the best fit for your approach to combat.
ME2 weapons - Assault Rifles
Mass Effect 2 weapons - Assault Rifles
M-8 Avenger (Available from the start)
The M-8 Avenger is the basic starter assault rifle, and although it has a reasonably high fire rate and low recoil, it also outputs low damage so can struggle if you don't add extra ammo power to it. Unless you plan to take advantage of the high fire rate, you're better off swapping out with the M-15 Vindicator which arrives early in the story or one of the DLC weapons.
M-96 Mattock (Available with included DLC)
The M-96 Mattock is pretty much the all-round MVP of assault rifles, as it incorporates a very high fire rate with extreme accuracy as well as dealing high damage. The only downside is the smaller magazine size and spare ammo capacity, meaning you'll burn through bullets fast and need a decent secondary weapon to fall back on.
Collector Assault Rifle (Available with included DLC)
The Collector Assault Rifle falls into a similar bracket as the M-8 Avenger, and although it has a higher damage output this is offset by a lower fire rate and ammo capacity. Its low spread can help players who like to get up close and personal, but there are better assault rifle choices available.
M-15 Vindicator (Available from Act 1 Dossier: Archangel)
The M-15 Vindicator is an absolutely solid choice for an assault rifle, as its high accuracy coupled with low recoil means you have a much better chance to pick off enemies with headshots in the heat of battle. However, it is limited to burst fire with no full auto option which makes it less suited to close combat, and with its smaller magazine and spare ammo reserve you're best off weakening enemies with powers before finishing them off with this assault rifle.
Geth Pulse Rifle (Available from Act 2 Dossier: Tali on Hardcore/Insanity difficulty)
Although the Geth Pulse Rifle delivers a high fire rate while maintaining great accuracy, its actual damage output is low but it can quickly destroy shields. This makes it a useful tool for breaking down enemy defences, however as you can only access it on higher difficulties its low damage capabilities mean you may struggle against tougher opponents if this is your primary.
M-76 Revenant (Available from Act 2 Collector Ship)
The M-76 Revenant can only be used if you select Soldier class for your Shepard, and choose it during the Collector Ship mission. It packs a ton of ammo in the magazine and reserves, however the low accuracy and high recoil make it a difficult beast to tame with its high fire rate. You can counter some of this with the Adrenaline Rush power, and should focus on close range combat while firing in quick bursts.
ME2 weapons - SMGs
Mass Effect 2 weapons - SMGs
M-4 Shuriken (Available from the start)
Although the M-4 Shuriken is a starter SMG, it can still be a useful weapon to have. Holding the trigger fires a three-round burst, which improves accuracy over longer range, though you can also keep tapping it for less accurate full auto fire instead if you're close to your enemies. The damage it outputs isn't high, but it is very effective at taking down shields and biotic barriers.
M-12 Locust (Available from Act 1/Act 2 Kasumi: Stealing Memory)
The M-12 Locust is unusual for an SMG, in that it has both high accuracy and low recoil. This makes it strong contender at mid to long range combat, which is useful as its lower rate of fire means it's less suitable for up close fights. Although not quite as effective against shields, the damage rate it can achieve against enemies is higher than many assault rifles, making it an excellent ranged choice.
M-9 Tempest (Available from Act 2 Dossier: Tali)
The M-9 Tempest is a step up from the M-4 Shuriken, as it can fire a five-round burst by holding the trigger rather than three. This helps with dealing accurate damage over longer ranges, however it also has a large clip capacity and an extremely high fire rate, which can make it a devastating weapon up close too. It's more effective against shields than enemies, though this can be offset with ammo upgrades.
ME2 weapons - Shotguns
Mass Effect 2 weapons - Shotguns
M-23 Katana (Available from the start)
The M-23 Katana is a basic starter shotgun, and although it deals a decent amount of damage to early enemies its slow rate of fire can leave you exposed. It won't hold up in later missions, so replace it as soon as possible.
M-22 Eviscerator (Available with included DLC)
The M-22 Eviscerator is an excellent pick for a shotgun, as the low spread of its shells allows for high damage to be dealt with a degree of accuracy. However, it does have a relatively low fire rate, and with only three slugs in a magazine you do need to plan your attacks so you don't get caught reloading in the open.
Geth Plasma Shotgun (Available with included DLC)
The Geth Plasma Shotgun is an absolute beast, and arguable the best shotgun available. It has the unique ability to charge your shot before firing, which both concentrates your projectiles and deals additional damage, while it's also extra effective against shields and biotic barriers. The only downside is ammo, as it has a small clip and spare capacity plus a fully charged shot expends two ammo instead of one.
M-27 Scimitar (Available from Act 2 Dossier: The Justicar)
The M-27 Scimitar is another top-notch shotgun choice, and definitely worth looking out for when you reach Act 2. As an auto-shotgun it has a very high rate of fire, which combined with a large clip size can completely decimate enemies, as long as you're prepared to get up close and personal with them.
M-300 Claymore (Available from Act 2 Collector Ship)
Although the M-300 Claymore is capable of dealing a high level of damage, there are several issues which make this a difficult shotgun to recommend. Firstly, its accuracy drops off very quickly over distance, so you need to be close to your enemies to get the full damage output benefit. Also, it only holds a single round in the chamber, and with a reload speed of several seconds after each shot you'll be left exposed during close combat.
ME2 weapons - Sniper Rifles
Mass Effect 2 weapons - Sniper Rifles
M-92 Mantis (Available from the start)
Although the M-92 Mantis is a starter sniper rifle, it's actually a great weapon for picking off individual enemies at a distance, as the high damage it deals can eliminate with a single headshot. However, because it's a bolt action rifle, there is a reloading delay after every shot which can cause issues when dealing with groups of foes.
M-29 Incisor (Available with included DLC)
The M-29 Incisor is particularly unusual for a sniper rifle as it fires in three round bursts, and its sizeable recoil makes it hard to maintain accuracy. The burst first also makes it harder to hit headshots with the second or third bullet due to your target moving, so you're better off aiming for torsos to make every shot count. Lower magazine and spare capacity make this weapon ammo inefficient, but in the hands of a squad member it can be annihilating.
M-97 Viper (Available from Act 2 Dossier: The Assassin)
The M-97 Viper is a semi-auto sniper, which makes it more suitable for use as a long range assault rifle than picking off enemies with single headshots. The large clip and spare ammo capacity mean you can afford to sink a number of rounds on an opponent, and although it's not as powerful as other snipers you can still drop them with two or three well-placed hits.
M-98 Widow (Available from Act 2 Collector Ship)
The M-98 Widow is an absolute monster of a sniper rifle, with a high damage stat meaning it can one shot kill many enemies even if you're hitting the upper difficulty levels. You do need to take into account that it's a single shot low fire rate weapon, so works best when methodically picking off opponents at a distance. It does lose a lot of power when penetrating shields and biotic barriers, so you should combine with specific ammo to offset this, or deplete their defences before following up with a heavy shot.
ME2 weapons - Heavy Pistols
Mass Effect 2 weapons - Heavy Pistols
M-3 Predator (Available from the start)
The M-3 Predator is the first weapon you get your hands on in the game, and therefore unsurprisingly it's not particularly impressive when compared to the other guns available. It does have the highest fire rate out of the heavy pistols, however its low damage output means you should ditch it as soon as you get the opportunity to upgrade.
M-5 Phalanx (Available with included DLC)
What makes the M-5 Phalanx stand apart from the other heavy pistols is that it has a laser sight equipped, allowing you to pinpoint where your shots will land with 100% accuracy. Combined with its relatively high damage output, this makes it a great weapon for lining up headshots on static targets no matter how far away they are.
M-6 Carnifex (Available from Act 1 Dossier: The Professor)
As with the Predator, there's not a lot about the M-6 Carnifex to make it stand out, though its higher damage output make it the superior choice from that pair. That being said, the Carnifex has a slower rate of fire and less ammo available, so is best treated as a fallback weapon if your main choices are out of bullets.
ME2 weapons - Heavy Weapons
Mass Effect 2 weapons - Heavy Weapons
Arc Projector (Available with included DLC)
The Arc Projector fires a high voltage electrical beam, which after successfully hitting a target can then chain to other enemies for additional shock damage. This makes it particularly effective against clusters of enemies, with the chaining attack able to move round cover and hit those not in your direct line of sight. The damage dealt will only slow down tougher opponents rather than eliminating them, meaning there are other explosive weapons that are more effective in those situations.
M-490 Blackstorm (Available with included DLC)
The M-490 Blackstorm is effectively capable of firing a black hole, with the singularity it creates drawing in enemies before explosively collapsing and sending them flying, and this blast is even powerful enough to damage opponents through cover. It does have a very long three second charge time before launching, as well as heavily limited ammo capacity, so is best used to target large groups of enemies in a restricted space so they're unable to escape the blast radius.
M-100 Grenade Launcher (Available from Prologue: Awakening)
The M-100 Grenade Launcher is the first heavy weapon you'll encounter in the campaign, and unsurprisingly its explosive output with splash damage makes it well suited to crowd control when facing groups of enemies. The grenades it launches travel in a straight line rather than arcing down due to gravity, which means you don't need to account for drop when aiming for targets further away.
Collector Particle Beam (Available from Act 1 Horizon)
The Collector Particle Beam generates a focused beam of radiation, which is highly destructive against shields, biotic barriers, and armor. Although it is very accurate and efficient with ammo, you do need to maintain a continuous line of sight with the enemy you're targeting, which leaves you exposed and is particularly risky on higher difficulty levels.
M-451 Firestorm (Available from Act 1/Act 2 Zaeed: The Price of Revenge)
The M-451 Firestorm is a particularly potent close range weapon, capable of delivering a high damage rate to shields, biotic barriers, and armor. It is highly ammo efficient and can maintain a steady flame blast without pausing to reload, however the fire it creates doesn't really spread between enemies so you'll need to target them individually.
ML-77 Missile Launcher (Available after researching one Heavy Weapon Ammo upgrade)
The ML-77 Missile Launcher is capable of rapidly firing projectiles, each of which has a seeking ability to acquire enemy targets and home in on them. You cannot control which opponents the missiles will target, which sometimes makes using this weapon rather unpredictable, however it is particularly effective against tough enemies that move erratically as you can fire multiple rockets in their direction before retreating to cover.
M-622 Avalanche (Available after researching two Heavy Weapon Ammo upgrades)
The M-622 Avalanche is a cryo weapon that fires rounds of super-cooled particles, which have a wide blast radius and can freeze any enemies they impact. Not only are frozen opponents briefly incapacitated and taken out of the fight, but other attacks become much more effective against them. Unlike the M-100 Grenade Launcher, the rounds from the Avalanche do arc downwards slightly due to gravity, so take this into account when targeting at a distance.
M-920 Cain (Available after researching three Heavy Weapon Ammo upgrades)
The M-920 Cain is an absolute monster of a weapon, and although its billing as a nuke launcher is technically incorrect as no radiation is involved, the high speed projectile launched creates the signature mushroom cloud upon impact. The frankly absurd amount of damage it creates over a wide area is offset by the four second charge time, and the ammo availability that means it can only be fired infrequently. This means you should save the Cain to use against a particularly tough enemy, as otherwise its effectiveness will be wasted.