The screen cap was taken by my brother while we were building together on our server. But building clearly wasn't the only thing I was doing. Can any of you take a guess at what did this to me? I'll give you a hint, it has nothing to do with the person who took the screen shot.

Spoiler- don't read the text below this, unless you really want to know what happened.

Answero
I was spam clicking with my gold sword while the magic spells bukkit plugin was active. Using the "volley" spell, I unknowing covered myself in arrows, and was told by my brother what happened. Only the other player was able to see it. It's completely invisible to the person who is covered in them.