Dummy spells hitting unseen units

I've been thinking about this for a while, and I thought of a solution but I'm hoping there's something better.

Suppose, for example, that you want to make a Mass Stormbolt ability, which is untargetted and when cast, creates dummy casters which stormbolt all enemies in range. The problem is that if you create a dummy unit for the caster of the ability and order it via triggers to stormbolt units which cannot be seen by the player (invisible) but are still there, then the unit cannot cast the ability and thus the effect is not done.

What I'm thinking of doing is making a neutral player have some type of 99999 range true sight unit, and the entire map revealed. All dummy units would be created for this player, but all ability damage would be done via triggers so that the caster of the ability would get bounty. Problems arise when you want the damage to be done upon the impact of the storm bolt, which gets into all kinds of complex timing systems in order to achieve a reasonable effect.

So basically, is there any better way of doing this? I havn't tried creating a detector for the owner of the caster for 0.00 sec (just long enough for ability to be cast) however I'm worried that invisible detection might not be timed precisely, similar to how fog of war works updating every .4 seconds, or how auras are not gained and lost precisely.

I've never used his caster system, but are you sure that his caster system does in fact do this? I don't want to download and set it up if it doesn't even answer my question

Offtopic: PLEASE change your avatar pic. Health risks aside, it is annoying as hell.

Expiration timer 1 second, 600 range truesight. IMO there's no better way.

If you don't change that damn avatar, then you can DIAF. THINK ABOUT THE HEALTH RISKS!

Deleted his post. As for the actual question, it depends on how complicated you are going to make it. You could have a neutral dummy unit cast a stunning stormbolt and trigger the damage for instance.