Honestly Rhode Island reds could probably top it off.One of my first two chickens were these two Rhode Island red hens and they would pick on my other hens,accept the ones who were higher on the order.But,eventually they turned our flock upside down and everyone acted off like they did.sadly,all those hens are dead.
So far,my most meanest hens have been our Silver Laced wyandotte and our 4 year old black sex link,she is a monster.