lots of different things.
I find that most times you can avoid the behaviour if you notice the triggers leading up to it...
My kids aren't 'naughty'... but there are a lot of them and they grate on each others nerves which leads to tension and lashing out either physically or with words.
Lots of reinforcing of positive behaviour and direct modelling "Jordan. Our family speaks nicely to each other. You can say "Julian, please watch your feet because it keeps knocking my tower" but you must not scream at him".
Oliver and Jordan get sent to their rooms for being sassy to me or their dad, or told to go and come back when they're ready to behave like members of our family...
Gabe and Julz aren't too bad... they get told off and that tends to work for them.
Lysander gets time out, but mostly just distracted.... he's only 2.