The Joker obviously didn't see the thing behind him at first. He was delighted to see the man dance like the little faerie he was. He turned to fire off a few more rounds, and that's when he noticed the duplicate.
"Oh! What a nifty little trick! The more the merrier!" The Joker giggled like a little sissy. And then his eyes went dark. "Well, screw this. I wanted to have fun with a body count, and a body count I shall have." The Joker aimed his gun at Sam's chest and prepared to fire.