I don't know, and I think watching someone die by your own hands would probably be one of the worst feelings in existance.
The largest thing I've killed was a female sparrow with a BB gun.. I was like 14
It was a horrible experience... We were shooting beer cans with a friends bb gun, and suddenly a small brown thing caught my eye in a nearby tree. My friend saw it too, and said "I bet you can't hit that bird" or something like that. I lined the sights up her. She hadn't done anything wrong.. and she surely didn't realize that she was about to die as she sat there, picking insects off the tree.. Most likely for a nest full of chicks somewhere. I thought about it for what seemed like a long time, and pulled the trigger. I don't know why I did it, but I did. I saw the BB fly out of the gun, and in the background, there she was. That moment is frozen in my mind, probably forever. The picture of the BB about a foot from the gun, with the bird still alive in the background.
A millisecond later, she fell from her perch in the tree. We ran over to her, and she lay on the ground, audibly gasping for air, spinning herself around in small circles as she flailed her wings and feet. At that point, I realized I had done a terrible thing.. Not only did I try and kill her, but I had failed.. and this poor creature was suffering greatly now. I knew what I had to do. As I picked her up, I saw that she was bleeding from a spot on her chest. I figured that I probably punctured one of its her sacs. As she struggled in my hand, gasping for air.. I grasped her head firmly, and flung her body towards the ground. She stopped moving, and lay limp in my hand, her neck broken. I dug a small hole in the ground, and burried her. let me tell you, I felt absolutely horrible... to the point of tears. I couldn't help but think that her babies could now be in jeopardy because of my senseless act.
The thing is, I've always loved birds, ever since I was a small child. I really don't know what posessed me to do that, but I'll never do it again.
I would hunt things for meat if I was trying to survive, but to kill or even hurt anything because it's "fun" is just wrong.