Targets Inside Area

Hy guys.
I'm trying to make a confusion spell with triggers. I got "Blizzard" as dummy (I made the "Issue order with no target":Stop so the spell effects won't work) but I can't get the units in the area of effect of the spell. How do I do it?

Thanks

P.S.: Another doubt: if I try to pick random 10 units in range near the caster but there is only one, or anyone, do I need to make some "exception" catching or WC engine already handles this mistake by itself?

P.P.S.: Ha, still another thing: "random number between 1 and 10" includes 1 and 10? I guess not but JavaScript (or Java, don't remember) includes the first and does not includes the second argument - it'd have 1 but not 10.

P.P.P.S: Arrays initial index is 0?

The initial index is 0, I don't know the other answers sorry.

I just spent a few trys perfecting this myself.
To grab the units inside an AoE just use the "pick every unit in a ___ raidius around target point of ability being cast."
Use pick every units matching condition if you only want enemy, alive, organic, etc. only units.

P.S. Don't remember exactly...

P.P.S. You know, I ran a few tiggers to figure this out, but all I don't remember. I know that it's not like Java - it either includes both or excludes both.

Happy hollidays.