Having spells revisit previously attacked units

I wanted to know if it's possible to make a spell to where it can attack an enemy unit more then once, otherwise all the leftover bounces going from unit to unit that I put on the spell will go to waste. I wanted to see if this was actually possible becuase I don't really like spells do a great deal of damage to one unit, and then never hitting them again. Anyone know if it is?

Examples:
1. Chain Lightning would deal 5000 damage without hitting it again(very lame) as compared Chain Lightning dealing 250 damage and is able to revisit a previously attacked unit.

2. Healing Wave able to heal 1000 health compared to healing 125 health and is able to revisit a previously healed unit.

Of course, if they're isn't another unit for the projectile to hit, it'll dissapear. I don't want the a unit getting hit from the spell from all of the bounces, then it would be like having Shadow Strike.

So basically, you are trying to create an "omnislash" effect?
You're going to need 2 variables for the target, and the spell animation dummy.
I'm a lil rusty with my world editor script, so here's a debrief of the triggering.
Variable ABC = Targeted Unit
Variable BCA = Dummy Animation Unit

First, in object editor create a dummy unit, based off a wisp or something (doesn't matter)
Give that object, the model of what projectile you want. Give the dummy the "locust" ability, and also make a custom ability based off of roar. Make the roar animation thunder clap, and modify it's target's to NO units. Modify the movement speed etc...
Name it wispies i guess? Doesn't matter.

Here's the trigger:
A unit finishes casting an ability.

The ability is equal to (Name of Spell, base it off of stormbolt for simplicity)

Create a custom unit of "Wispies" at position of casting unit
Set CBA = last created unit
Set ABC = target of ability
Order CBA to move to position of ABC
wait for condition: CBA is within 25 range of ABC checking every .2 seconds.
Order triggering unit to damage ABC for "100" damage.
Order CBA to cast "Night Elf - Druid of Claw - Roar"
Set ABC = random unit owned by owner of ABC within 400 range of CBA
Order CBA to move to position of ABC
wait for condition: CBA is within 25 range of ABC checking every .2 seconds.
Order triggering unit to damage ABC for "100" damage.
Order CBA to cast "Night Elf - Druid of Claw - Roar"
Set ABC = random unit owned by owner of ABC within 400 range of ABC

.... Repeat as many times as you like...
Remove CBA from the game
Set ABC = no unit
Set CBA = no unit

Make sure the cooldown for this spell is longer than it's effect, else the trigger will be all messed up.


So basically, in summary ur dummy unit is a projectile, that runs in circles creating a thunderclap animation whenever it deals damage.

It's not omnislash, I was acutally going to make a Chain Lightning.

Read the actual trigger... I said omnislash EFFECT. In other words, random units in an area take damage.
Sigh why did i bother helping you... especially when you wouldn't take the 60 seconds to actually read the trigger. not like you understand it anyway.

I did read the trigger, I was just trying to tell you I was going to use what you said to actually make a Chain Lightning!