There is an emotion that is not human but is. We just don't recognize it as such. In the degrees of Shifu we have always called it "Becoming the Beast". That refers to the feeling in each individual beast. But there is a more generic form of it we can call "The Beast". If we train in the right way and with a good heart we can achieve it. 

Dr Jordan Peterson often refers to being a monster under his own control. This is that. This is how that is achieved. It is a thing of immense personal power.

Note: The book I referred to and couldn't remember is called "Thick Face, Black Heart"