Cloaking Aura

I need help making a cloaking aura, like the Arbiter in SC. I have been doing is adding a permanent cloak ability to any unit with (some #) of the Arbiter. But i can't get a trigger that removes the spells when they move away from the Arbiter. Plz only reply if you have made a way that works, instead of a guess of what i should do because I have already tried many things.
THX

Not 100% sure, but you may be able to make the Permanent Invisibility Skill a "Aura" class ability with a range you set, but I'm not 100% sure. You may want to check it out, just in case.

Permanent Invisibility+ ghost == CLoaking

Anyways, you need a unit group variable CloakedUnits, also give the arbiter an aura and give that aura a custom buff called Cloaking aura:

Events:
Every 1 second

Actions
custom script : set bj_wantDestroyGroup=true
Unit Group Pick every unit in ( all units matching ( (matching unit has buff Cloaking aura equal to true ) ) and do:
-- Add Permanent Invisibility to picked unit
-- Add Permanent ghost to picked unit
-- Add Picked Unit to CloakedUnits
Unit Group Pick Every Unit in CloakedUnits and do
If Picked Unit has buff Cloaking Aura equal to false
then
Unit Remove Permanent invisibility from picked unit
Unit Remove ghost from picked unit
Unit group - Remove Picked unit from CloakedUnits
else
Do nothing

Thx, your reply helped.

This is what i ended trying:
Twilight Aura
Events
Time - Every 1.00 seconds of game time
Conditions
Actions
Unit Group - Pick every unit in (Units within 1000.00 of (Position of Lunar Priestess 0004 <gen>)) and do (Actions)
Loop - Actions
If (All Conditions are True) then do (Then Actions) else do (Else Actions)
If - Conditions
((Picked unit) is in Cloaked) Equal to False
(Picked unit) Not equal to Lunar Priestess 0004 <gen>
((Owner of (Picked unit)) is an ally of Player 1 (Red)) Equal to True
((Picked unit) has buff Twilight Aura (Lunar Priestest)) Equal to True
Then - Actions
Unit Group - Add (Picked unit) to Cloaked
Unit - Add Permanent Invisibility to (Picked unit)
Else - Actions
Unit Group - Pick every unit in Cloaked and do (Actions)
Loop - Actions
If (All Conditions are True) then do (Then Actions) else do (Else Actions)
If - Conditions
((Picked unit) has buff Twilight Aura (Lunar Priestest)) Equal to False
Then - Actions
Unit Group - Remove (Picked unit) from Cloaked
Unit - Remove Permanent Invisibility from (Picked unit)
Else - Actions

It worked for 2 sec than my aura messed up and didnt show on any affected units.

Just do it like he said. It's only going to effect the units within aura range, anyway.