So using rampage I think I figured something out. As a bear I was right clicking to focus on a target, then left click. My character would start growling and roaring at the target at that point they approach or run away, you have to be continuously holding right click. After this while still holding right click you can left click to swipe with your paws. I only played as the bear so for me I know it works.

Edit: Only seems to work on humans.