For verbal abuse, my kids have been taught to ignore, walk away, get an adult. If someone is physically attacking them, they have the right to stand their ground, and show their strength, however it takes to do it, whatever it takes to show that other person that they have to stop and they mean business. Sadly, some people only understand physical language, and while I wish it wasn't that way, my kids deserve to be safe from violence.
Kalki is the target of bullies all the time on the field in his rugby games, cause he is d.amn tough, and usually twice the size of anybody else on the field; so they all work to take him down. He has carte blanche to do what it takes to show them he is not intimidated by them. He is such a softie, though, that they frequently get away with the most horrible stuff.
I have footage of Kalki being clotheslined by this awful little kid, the coach's son of the opposing team, with the worst hit the officials and the ref had ever seen. And then five minutes later, another opposing player hit him again across the throat, and told him to suck it up. Behavior like that I have absolutely no problem with letting them take the consequences. (BTW, the other coach seemed to encourage that behavior, and all the officials and the ref were so shocked they had no clue how to deal with it....the adults in your life are not always going to be able to deal with the problems, so you need to be able to deal with things yourself, too)