Well you just have to edit the spell targets allowed. The basic Blizzard has no targets checked which means that it targets everything. If you want it to damage only enemies you can check in Targets Allowed the fields which read Ground and Enemy and it will target these types of units. If you want you can check air and it will target air units too.
I'm on a page about incorrect corrections, and spent the better part of like two hours trying to get someone to understand that -5^2 = -25, not 25, and then that post had comments get reposted because that group is self sustaining, and that person was in turn trying to explain what I just explained to them. And I'm taking that as a victory
I will be AFK for a couple of days you guys hold down the fort while I am gone. I will be checking in on my phone but that will severly limit me. Be back saturday!