Ok, I tried to make a similar spell called Cloak of Fear. It is like Immolation spell and works greatly but unfortunately lags a lot. Perhaps my computer is the problem (I have a pentium II at 533Mhz so it kinda sucks). So, if this doesn't bother you I can help you with the spell I made, if you like the variant. So, as Vexorian says, you would make the units flee in panic for a couple of seconds. Depending on the level, it runs for more seconds. But I beleive it is a little bit too overpowered. Take Immolation for base, Change buffs, AoE to 0, icons, effects. Change damage to 0. I think that's all for the skill, oh and change name to Fear. Ok, now let's go to triggers.
Fear
Events - A unit Is Attacked
Conditions - ((Attacked unit) has Fear buff) equal to true
Actions - If, Then, Else (Multiple Actions)
[NOTE: I will make the If, Then,Else for first level only. Just change the level from IF to 2 respectively 3 and the number of waiting seconds to 2 respectively 3).
IF - (Level of Fear for (Casting Unit)) equal to 1
THEN - Unit - Change ownership of (Attacking Unit) to Neutral Passive and Retain Color
- Order (Attacking unit) to Move To ((Position of (Attacking Unit)) offset by 250 towards 0.00 degrees)
- Wait 1 seconds
- Unit - Change Ownership of (Attacking Unit) to (Previous Owner) and Retain Color.
That is all. Though the last line may be changed a little by giving an integer value to the unit, the value being equal to the number of the owner of the unit. You would then change ownership to player with index value, where the value would be the integer value of the unit. Well, i gave you this alternative since it's faster but it can cause problems if the target is affected by Charm. I may found a solution for this as well.