Targetting only Summoned Monsters

Is there anyway for spells to target only summoned units? I know it was possible to do it before, but i guess some patch removed that function.

I don't know how to make it target summoned units only by setting to to attack summons only directly, but you could work around this by setting unit classification of all summoned units to mechanical or something and then make the spell target mechanical units only.

Pyrus, how have you tried to make something target only summons? I'd like to know where you're at before I try it.

I remember at some point I was able to select "summons" in the target allowed field. Now I cant. I know about the "ancient" loophole, but to me that method is ugly as you see your summons have the ancient status in the UI.
I just tried it with the Suicidal Classification and Storm Bolt, and that seemed to work. Now the question is does the suicidal classification do anything to the units?

I don't believe so. I used to think that Suicidal made the units unable to enter Zepplins, but I never researched it. I've been using it for a spare classification in several areas.