[General] Unit ignores unit

[RG00]

Is it possible to make a unit ignores a specified unit if he is attacking-moving to a position(without giving invulnerability to that unit)?

 

[Sieben]

You can make attacking unit's owner treat the other one's owner as allied (change owner if needed)
Or you can disable attack ability for attacking unit while standing close to ignored unit (you can disable attack by using a spell based on Silence for example, or Cargo)
Dunno if it helps!

 

[RG00]

You can make attacking unit's owner treat the other one's owner as allied (change owner if needed)
Or you can disable attack ability for attacking unit while standing close to ignored unit (you can disable attack by using a spell based on Silence for example, or Cargo)
Dunno if it helps!

I can't do these things unfortunately.
Basically the situation is: there is a gate which is a unit, enemy units will try to destroy it as a first objective. The problem is that the player has the control of the gate for opening and closing it(when the gate is open it's invulnerable and units can cross it) so, if enemy's units cross the gate they will start go attacking-move to the next objective but, if the player close the gate they will just come back to attack the gate, which makes no sense at all XD, the gate should be attacked only from enemy units that didn't manage to cross it.