Blizz, wouldnt you have something like this for Blizz-ABS already, like some sort of Auto Targetting Projectile, like Magic Missle that just hits the closest target Auto-*ahem*-Magically?
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Okay, think I could talk someone into writing a script to do this? I can do it myself, but, hopefully this should be challenging enough for up-and-coming scripters to get in some good practice...