Give it a gun related name like lead
Lead will have high armor and health but low shields.
Power 1 - steal one enemy's ammo to replenish your own and force the enemy to reload,leaving a brief attack opportunity. Similar to loki's radial disarm, but it affects one foe and gives you ammo, best for bullet guzzlers like boar prime and wraith twin vipers.
Power 2 - next shot fired explodes and knocks enemies down
Power 3 - current clip shots will auto hit enemies even normally missed shots, aka homing shots, no extra damage though.
Power 4 - all shots you and squad mates fire are automatic critical hits with min of +50% damage up to +200% damage. Cannot be combined with power 3, using one will end the other.
alternative power 4 - squad gets plus 25% to 100% damage with guns and damage ignores armor/shield defenses completely, like shooting a lvl 1 enemy, combine this with crit soma gun builds, nova's molecular power to slow enemies are blow them up, and banshee's sonar to mark weaknesses that cause upto 4x damage when hit, and you'll be taking down lvl 60 and above enemies much easier.
Seems i attracted alot of trolls, this is only an idea underconstruct, i'm looking for good feedback on useful changes to make this idea better.
Updated since comment 28