How to take no damage from non-melee creatures
This strategy will work against any creature which doesn't use melee as its primary attack (like Witches or Minotaur Archers).
You just have to stand one square up or down from the entrance in a building-like structure without windows. This will force the creature to stand on the entrance square, which means next to you, because there's simply no other square on which it can stand to reach you with its attacks. The problem for those creatures is that they don't even want to stand next to you, they want to attack you from a distance, so they will retreat to the square in front of the entrance again. But when they're on that square, they can't reach you with their attacks once again, so they go back to the entrance square. In this way they will just be going back and forth between the entrance square and the square before it, and they won't even do any of their attacks. So the only thing you have to do is to make sure you've got the creature targeted (without 'Chase opponent' on of course!), and you will kill it without receiving any damage.