Entity attack condition causes crash

I am trying to make entities that behave aggressively towards any living entity except for themselves. I have been trying to achieve this through a condition that checks for if the attack target has the specific tag or not. Each attempt to use the tag system has resulted in instant crashes from a null being called. I have looked everywhere for a solution, but everything keeps pointing to the use of the [get entity [event/target entity] is targeting for attack] which is CAUSING THE CRASHES IN THE FIRST PLACE.

Is there a way I can get the entity to attack anything that lacks the tag without using the [get entity [event/target entity] is targeting for attack] procedure block?