Making Ability Questions

I need some help to make a Frost Nova ability that temporarily freezes (Entangling roots) all enemy units within a certain range (maybe 300) of the hero who is casting the spell. I need suggestions on how to do this through the object editor or through triggers.

For the first one, use a dummy and cast mass impale with different effects, that's the simplest way.

Second, try using the barrage ability I think that we have a tutorial about making multishot spells, but I am not sure.

Ok, Ill try that.

Oh, and I found the multishot tutorial and I meant to edit that out of my post. It must have not worked.

Blade.dk, I guess the simpliest way is war stomp.