I really don't know. With you, somepony would just get hooved to death. Sure, they would get broken bones and all, but it's just blunt pain. The bear has paws and claws though, so he could rip limbs off, or dig into their spine using his claws. He could also eat them.
Anonymous

I’ve heard that when you’re decapitated the head lives on for a few seconds before you die.

Think about how much time slows down when you’re terrified; how long a few seconds can be stretched out.

But we’re getting ahead of ourselves. I wouldn’t kill anypony just for hurting Sweetie Belle. I imagine disciplinary action would be enough.