How prevent from Illusions(Mirror Image) Drop items ?

[streng]

Hi guys.
I have a problem. I create creep on my map , which has mirror image skill. The problem is that when image dies drop items like regulary unit. Is any way to prevent from this ?

I used this drop system triger, but condition "summoned unit" dont work

Wolf Elite 1
    Events
        Unit - A unit Dies
    Conditions
        And - All (Conditions) are true
            Conditions
                (Unit-type of (Triggering unit)) Equal to Gray Wolf (Elite)
                ((Dying unit) is Summoned) Equal to False
    Actions
        Set Item_Drops = (Random integer number between 1 and 3)
        If (Item_Drops Equal to 1) then do (Item - Create Tome of Strength at (Position of (Triggering unit))) else do (Do nothing)
        If (Item_Drops Equal to 2) then do (Item - Create Tome of Agility at (Position of (Triggering unit))) else do (Do nothing)
        If (Item_Drops Equal to 3) then do (Item - Create Tome of Intelligence at (Position of (Triggering unit))) else do (Do nothing)
        If (Item_Drops Less than or equal to 3) then do (Item - Create Herb of Recovery at (Position of (Triggering unit))) else do (Do nothing)

Ok guys problem is slolved. Sorry for post. Finally find condition Unit is a Illusion

 

[keychup]

nice