I’ve had a couple nasty roos and several very sweet roos. Culling a nasty one isn’t giving up, it is saving yourself a whole lot of trouble and a potential lawsuit. If you have an aggressive roo that attacks a neighbor/child/visitor, prepare for trouble. Especially with small children! Believe it or not, that animal that is 5 times smaller than you CAN cause serious injuries and potentially even death to a small child. If you really want to stick with this rooster, DON’T hit him or defend yourself. In his eyes this makes you something he can fight. You’ll just be throwing gas on the fire. Instead “fight” him in a way he has no clue how to retaliate to. Every time you walk into the coop, pick him up and hold him tightly. This puts him in a position of submission and humiliates him in front of his hens. He may be too old to get this lesson, but it is your best chance of stopping this aggression without culling him.