Heavy Pistols
M-3 Predator Heavy Pistol
Details: Reliable, accurate sidearm. Effective against armor, weak against shields and biotic barriers.
Unlocked: First mission, any class.
M-6 Carnifex Hand Cannon
Details: Highly accurate and lethal sidearm. Effective against armor, weak against shields and biotic barriers.
Unlocked: Given by Mordin during his mission.
SMG's
M-4 Shuriken Machine Pistol
Details: 3 round burst. Effective against shields and biotic barriers, weak against armor.
Unlocked: Base SMG
M-9 Tempest SMG
Details: Full auto. Effective against shields and biotic barriers but weak against armor.
Unlocked: Tali's recruitment mission, near beginning of level.
Assault Rifles
M-8 Avenger
Details: Fully automatic. Effective against shields, armor, and biotic barriers.
Unlocked: Base assault rifle
M-15 Vindicator Battle Rifle
Details: 5 round burst. Effective against shields, armor, and biotic barriers.
Unlocked: During Archangel recruitment mission, nearby after reaching Archangel
M-76 Revenant LMG
Details: Unleashes a storm of deadly high velocity slugs. Less accurate than an assault rifle, but deals much more damage.
Unlocked: Available only to soldiers when choosing advanced weapons training. Not missable, part of the story.
Geth Pulse Rifle
Details: Fires a rapid stream of high energy phasic slugs. Very effective against shields and biotic barriers.
Unlocked: End of Tali's recruitment mission, after defeating the geth colossus. Must be on Hardcore difficulty or harder.
Shotguns
M-23 Katana Shotgun
Details: Common military shotgun. Deadly at short range, but ineffective at long range. Very effective against shields and biotic barriers, but weak against armor.
Unlocked: Base shotgun
M-27 Scimitar Assault Heavy Shotgun
Details: Rapid fire Shotgun. Deadly at short range, but ineffective at long range. Very effective against shields and biotic barriers, but weak against armor.
Unlocked: During Samara's mission, near Elnora
M-300 Claymore Heavy Shotgun
Details: Rare krogan shotgun. Deals high damage at short range, less at long range. Effective against shields, armor, and biotic barriers.
Unlocked: Researchable prototype usable by Grunt by talking to him, only usable by soldier or vanguard Shepard during advanced weapons training.
Sniper Rifles
M-92 Mantis Sniper Rifle
Details: Powerful Sniper Rifle. Accurate at long range, but has a slow rate of fire. Very effective against armor, but weaker against shields and biotic barriers.
Unlocked: Base Sniper Rifle
M-97 Viper Sniper Rifle
Details: Semi-automatic Sniper with higher ammo capacity. Highly effective vs armor, somewhat effective vs. shields and biotic barriers.
Unlocked: Thane's recruitment mission, near the beginning.
M-98 Widow Anti-Material Rifle
Details: Deadly accurate anti-material rifle. Especially effective against armor, but also against shields and biotic barriers.
Unlocked: Researchable prototype usable by final squad member by talking to him, only usable by soldier or infiltrator shepard during advanced weapons training.
Heavy Weapons
M-100 Grenade Launcher
Details: Rapid fire grenade launcher.
Unlocked: During first mission, story event.
ML-77 Missile Launcher
Details: Rapid fire missile launcher, seeking missiles.
Unlocked: Researchable prototype.
M-622 Avalanche
Details: Fires a freezing blast within a 5 meter radius.
Unlocked: Researchable prototype.
M-920 Cain
Details: Nuke Launcher.
Unlocked: Researchable prototype.
Collector Particle Beam
Details: High damage particle laser.
Unlocked: Horizon, close to beginning of level.
M-451 Firestorm
Details: Mid-Range flamethrower
Unlocked: Midway through Zaeed's Loyalty mission, after the morale choice.