Carried by the batarian military's notorious Special Intervention Unit, the Raider is a semi-automatic shotgun that loads slowly but fires rapidly, with tremendous force. Short-range even for a shotgun, the Raider has a large pellet spread. Rather than eliminating recoil, its integral compensators instead make it predictable and vertical.
The AT-12's main strength is in its unrivaled firing rate. This makes it perfectly suited to quickly bringing down armoured foes, but its low clip size and long reload time make it less prudent to use on smaller enemies. The reload time can be decreased to roughly 1 second through reload cancelling. This makes the AT-12's damage per second second only to the Piranha Assault Shotgun as well as eliminating a serious flaw with the AT-12.
The AT-12's spread makes it useful only in close combat, making it an excellent choice for Vanguards and anyone else engaging in close-quarters combat.
This weapon complements the N7 Destroyer well. Devastator Mode, when evolved with the proper ranks, will increase accuracy, eliminating one of the Raider's main drawbacks.
Infiltrators will be able to use their Tactical Cloak ability to move into the weapon's effective range undetected. This, combined with the damage bonus, can yield promising results. Because of the Raider's high rate of fire, the player can fire both shots while still benefiting from the cloak's damage bonus.
Adrenaline Rush's instant-reload function can be exploited ruthlessly to give this weapon unsurpassed DPS. Four shots in quick succession will likely kill or severely damage even the hardiest enemies. This tactic may also make the Raider more effective at dealing with groups of enemies.
Despite the small improvement shown by the weapon statistics, a level V Smart Choke does produce a fairly noticeable decrease in cross-hair width, making the weapon effective at slightly farther distances.
The High-Velocity Barrel will mitigate the problem of 'choice'. Before, you would have to choose whether to sacrifice accuracy, damage, or penetration. The HV barrel will enable you to keep your damage AND allow you to penetrate thin cover, or the shields the Guardians carry. Combining said attachment with the Smart Choke will then give you the means to counter-act the main problems of the AT-12 Raider.
Drill rounds or Armor-Piercing rounds will mitigate the loss of damage when shooting through certain levels of cover, or a Guardian's shield, proving an invaluable edge. This means one can forgo the use of the High-Velocity Barrel, as it weighs you down 50 points, something that can make a significant impact on power cooldowns. Armor-Piercing rounds also has a better degree of armor reduction depending upon the ammo level, potentially eliminating the need for a Shredder Mod.
Lagging can result in the Raider firing more shots than what the magazine can hold, with all shots being able to damage targets.
Resilient enemies can be slain quicker by aiming low then firing twice in rapid succession. This unites the Raider's high recoil and firing rate by aiming only once instead of twice.
The Talon Mercenary, when evolved to use the omni-bow for ranged attacks has problems at short range or when surprised. As the slow reload is not as much an issue, the high damage output, coupled with a melee blade attachment makes this the perfect on-the-spot weapon for them.