The Alliance Infiltration Unit is modeled on the Cerberus synthetic Eva that Commander Shepard's team discovered on Mars. Quantum blue-box AIs are considered illegal by the Council, but the Alliance has secured a special allowance to deploy the infiltration unit in this time of need.
Alliance Infiltration Units favor shotguns and are designed for close-quarters combat. They are durable and able to self-repair when downed.
The Alliance Infiltration Unit is built for close-quarters combat, with the fairly short-range power Snap Freeze, its version of Tactical Cloak, which can grant bonus shotgun damage on Rank 6, and the invulnerability power Repair Matrix.
Repair Matrix is a powerful survival tool for this kit. It works in a similar manner to Stimulant Packs, with the added bonus of an instant revival if downed during the duration of the power. Repair Matrix also gives a very brief moment of invulnerability. This allows the Infiltration Unit to get up-close and personal with enemies without fear of wasting too many consumables. It should be noted however if you are "Sync-Killed" you will NOT get back up, so be cautious around sync-kill enemies, but not too cautious.
The Alliance Infiltration Unit serves as an excellent support/revival class. Since Repair Matrix prevents you from being knocked out, the Alliance Infiltration Unit's natural speed allows it to easily reach downed players.
This unit can do a "one-two punch" of sorts by freezing an unprotected enemy before unleashing a powerful Omni-Blade attack.
All-in-all, the Alliance Infiltration Unit is one of most well-balanced kits available, combining maneuverability and high damage with survivability and squad support.
The AT-12 Raider is very effective in tandem with Tactical Cloak and Snap Freeze. You can easily fire the two shots off from the raider, then fire off Snap Freeze immediately afterwards. If timed correctly your gun will still reload as if you initiated the reload as your firing the Snap Freeze, all while potentially decreasing the cooldown time and being able to keep an almost constant flow of gunfire and Snap Freezing.
There is a glitch with the Venom Shotgun where releasing a charged shot will not break cloak. This can allow the AIU to fire off 1-2 additional shots with the boosted damage, depending on whether you choose to fire off a Snap Freeze or not, allowing the AIU to become an effective grenadier.
After firing a shot while in Tactical Cloak it is possible to quickly cancel into a Snap Freeze, allowing for a player to utilize the damage bonus of the cloak for both the weapon and power damage while still only suffering one cooldown. When used in tandem with a weapon such as the Wraith, you can do massive amounts of damage and continually control the field by freezing enemies.
Snap Freeze is extremely effective against almost every enemy, with only Phantoms shrugging the freezing effects, although they can still be chilled. Atlases and Dragoons can have their armor weakened, softening up these tough enemies for your allies.
Snap Freeze will hamper the armor of Praetorians and Scions. It'll also freeze unprotected abominations, providing you with valuable time to neutralise said enemies from a nice safe distance. It'll also deal with Collector troopers but you may need to decide whether its better to take a few shots, or take an explosion.
If scions are roaming the area, you may want to activate a Repair Matrix beforehand, while in cover, so that you wont run the risk of being stun locked so you cant use your Matrix before you go down.
Repair Matrix is much more useful here as there are no enemies that can sync-kill you. So long as you can maintain the Repair Matrix, it will be nigh impossible for the Geth to take you down.
Snap Freeze has little effect on most enemies until their shields are stripped. Pyros and Primes can be softened up while the rest can be frozen when their shields are gone.
Care should be taken, when using Repair Matrix, or any power, ideally, you should stay behind cover, so that your snap freeze gets fired and has its effect, and Repair Matrix so that if enemies stun lock you, you will not be unable to get back up.
Snap Freeze will hamper the armor of the Brutes, Ravagers, and Banshees and freeze all other enemies. Its particularly effective against Husks, as they can stop you from using your Repair Matrix which can become your worst nightmare.