I do not believe animals can be intentionally cruel anymore than they can be intentionally compassionate, wolves kill for sport, I have seen it. As pointed out cats kill for sport, the cat killing dog however, I do believe is learned behavior because very few act like this, unlike cats. One thing no one here has mentioned is boredom, and many animals act badly (in our opinion) out of boredom. Wolves in an area of excess wildlife, where they are not just surviving, will kill daily because they can. I have seen the moose corpses with almost no meat consumed, and then another the next day and so on.
Cats don't care if it is a mouse or a ball of string or a golf ball, it is something to stave off boredom. The fact that it's play causes harm to the mouse is completely irrelevant to the cat and it will throw the ball of string or tennis ball and bite it, just like it does the mouse or gopher.
That bison footage was not what it appeared either, the bison coming in from the rear was charging the wolves, and quite likely attempting to assist the herdmate, it just didn't work out and the herdmate zigged when he should have zagged..........oops wolf lunch, "sorry 'bout that Ralph, thought you were gonna break left when I hit the back wolf" Bison are noted for their herd protective behavior, so I believe this was a rescue attempt gone wrong.
I do not believe that an animal has the mental capacity to form the thought process to constitute "cruel intent".