Answer:
I am the ultimate killing machine used not once but TWICE I can be made by humans.
What bone has a sense of humor?
I have thirteen hearts but no body or soul. What am I?
I run up and down the stairs without moving. What am I?
I come in variety of colors and am found almost year round. My house is tall and my only fear is the cold. What am I?
What gift should you give blind people, drunks, and nerds for Christmas?