I'm upset at my friend who pretended to throw a rock at my motorcycle as I drove by.
What are you going to do about him?
I could really see myself killing him. I literally saw red when I saw what he did.
It sounds like he was joking but it was a dangerous joke. You should tell him that he upset you so he doesn't do it again, but don't dump your anger all over him as it can be hurtful.
Nah, I'm going to hurt him. I told him that I'll kill him.
Anger is okay, but reacting to that anger with hostility towards your friend is not okay. Wait to let yourself calm down before you go and talk to him about this dangerous stunt so that you are not mean and cruel in the process.