How do I repeat a trigger once?

I have an enemy that once it detects the player, it alerts all the other enemies. i have it set up so that when the global boolean is true, it triggers all enemies to attack the player. But i have it set to trigger once.

So i want to know how i can repeat this.

Trigger once doesn't mean once forever but it is more like a trigger event. If you set the variable to false and then true again at another time it will trigger.

Thanks lionz, i dont know why i didn't think of that.