Unit: Unselectable, but target of attacks

Hi, I have a little problem and I hope you can help me with this:

I want to make a unit unselectable, but I want the unit to still be able to get targetted by other units.

I tried the ability locust (aloc), It made the unit unselectable but also un-targetable.

Create a trigger like this:

E
A player selects (unit)
C
Ø
A
Clear selection for (triggering player)

I can't believe I didn't think of that before.

Thanks a lot man.