I had a terrible dream once where I watched as a large group of prison inmates were lined up in rows and stood there as they were shot at with canon balls. They all got torn to pieces, it was so gross.
I only killed once in a dream, it was a friend I had the hots for. He sat next to me on my couch and looked so good dressed in a tuxedo. I pulled a knife and stabbed him in the back. I felt guilty about it though and woke up, but the thought of him dead in a tux was so hot I tried falling back asleep and finishing the dream. It didn't work.
In another dream I had, I found myself chasing after two hot girls with a knife just like in the slasher flicks. I was almost catching up when I realized I was being chased by something as well, much larger and scarier. I was too scared to turn and look so I just ran and forgot about the girls.
I always wake up scared when I dream like this and then I have to check all the doors and windows to make sure they're all locked tight.
Just last night around 4 in the morning I suddenly awoke in a panic and my heart was racing. I was terrified and I thought I was having a heart attack but it went away quickly. I don't remember what I dreamt, if anything. I couldn't sleep thinking it might happen again. I'm even scared right now.