There are some layers to this question. Garryth2 feat reads:
When an enemy model advances and ends its movement or is placed in Garryth’s control range, one friendly Faction model in Garryth’s control range can target the enemy model with a basic attack. Zero Hour attack rolls are boosted. A model can only attack as a result of Zero Hour once per game. Zero Hour lasts for one round.
So a unit enters his control area. That movement is simultaneous.
First I read this feat that despite then showing up simultaneously I do get to make an attack at each model in my control range correct?
Next assuming I get to attack each model how does declaring attacks work when they appear simultaneously? Do I choose a model to make an attack with, complete the attack, and move on to the next model? Or since they appeared simultaneously do I need to declare all the attacks then roll them all?
Finally if I need to declare all the attacks then roll them all what happens if an attack kills multiple models? For instance I declare friendly model A will attack enemy model X and friendly model B will attack enemy model Y but then model A’s attack kills both model X and Y. Does model B get to make an attack later in my feat turn or has his attack been used to despite never actually being made since the attack was declared?
Hope that was clear any confirmation would be appreciated