autocast, but cannot be manually cast

[The-Rave]

I want make a simple spell that it's autocast, but cannot be disable the autocast, and has not icon.

i want it to be ability on buildable building.

 

[Pyritie]

So sort of like an aura ability with no icon?

 

[The-Rave]

So sort of like an aura ability with no icon?

I want to make spawn tentacle (like forgotten one's ability) and cast only when enemy comes near.