You focus on an enemy and fire a series of shots towards their position, forcing them to choose between taking cover or being perforated. Designate one enemy you can see and have line of effect to that is within range of this ability. They can use their Reaction to Stride or Step, or a Free Action to fall Prone. Once they have done so, or chosen not to do so, you can make 1 attack with the Aetherlight Beam (Repeater) ability against them. If they are not Prone or behind Cover when you make this attack, you can make +3 additional attacks with that ability against them, and this ability ends.
Until you attack another creature or the start of your next turn (whichever happens first), your designated target suffers a -2 Penalty to all of their attack rolls, and whenever your designated target uses a Movement or Attack action you can make 1 attack with the Aetherlight Beam (Repeater) ability against them as a Free Action. This includes actions such as Step that normally do not provoke Reactions.
If you spent any charges of Aether Flux to grant yourself additional attacks with this ability, you make those extra attacks as part of the initial attack against the target.