John slays the bear cubs
John rushes to the throat of the cub
And squeezes as hard as he can with his teeth (the cub whimpers in his pain)
After this...
..John throws him in the air
And breaks his neck
John attacks the other cub and sinks his teeth in the throat
A common effect: "Blood spills"
Finally he pulls himself off the cub, and blood spills from the dogs mouth, which he seems to enjoy.