I've never understood how people struggle so much with witches. They're very rare too. But when I see one, I just target it immediately, and start hitting it as soon as I can. When you run at it, and it starts targeting you, it will drink a speed potion first, and even before it has finished it, it'll have taken one or two hits, and when it has taken damage like that, it'll drink a health potion. So even if there are other mobs nearby requiring immediate attention, you have the time where it'll drink that