Is it possible to add a netrual mob type?

Is it possible to add a netrual mob type? As of right now, you can't exactly make a neutral mob(spawns in day light, attacks when hit), as when I make it Creature in: Behavioral Characteristics, and then make it creature type in Spawning, the mob doesn't play my attack animation, and it says in Behavioral Characteristics that creature type may crash or not work if it has an attack. While making it like a monster is a work around, it still doesn't spawn the same as a creatur would.