As ZerGreenOne said, you can use a dummy unit that has no model. (Art - Model File = Blank)
and give it a locust ability. So It will be invulnerable and has no collision.
You can then either make a temporary dummy - By giving it an expiration timer so it will be auto-
removed once the timer expires as ZerGreenOne said - or a permanent dummy which you can
make at map init and is used anytime whenever it is needed.
I really recommend you to learn variables, they are very useful and helpful in triggering.
Make sure the dummy can cast the ability. (No Cooldown, No Mana Cost, 9999 Range)
If it still doesn't work then we should find a workaround for the order problem.
Edit:
Found the workaround. Use this:
-
Custom script: call IssueTargetOrderById( YourDummy, 852609, AttackedUnit)
YourDummy must be inside a variable. Let's say the variable name is "Dummy".
In the custom script, it must be written as "udg_Dummy".
AttackedUnit must also be inside a variable. Let's say the name is "Target".
In the custom script, it must be written as "udg_Target".
852609 is the order string of Healing Salve.
This is an example:
-
Custom script: call IssueTargetOrderById( udg_Dummy, 852609, udg_Target)