Stay away from my rump.

LMAO! I was actually using some of my knowledge of the show there. I remember one of the episodes my daughter was watching was something about how every pony eventually gets a mark that shows up on their rump, and it's a sign of what they are going to be like, or something. So I figured branding you with an "evil" pony mark would make you an outcast, and leave you to side with Discord. No Princess Celestia for you!
Pranks do lose something when repeated, although I would have paid good money to see your expression when you realize this forum had a pony prank too.
As for branding other forum members, not only can I not approve of this I'd strongly recommend going anywhere near that end of EvilFish.
LOL. Yeah, I was in complete shock. I ran from GITP to here, thinking "It's ok, I have CD, I'll be safe there", only to find MLP everywhere. Open-Mouth Slack-jawed expression of disbelief. I then went and loaded up Skyrim, pretended everyone in Whiterun was a pony lover, and annihilated everyone. Unfortunately it would appear as though Princess Celestia was protecting a good many of them, lots of unkillables that ganged up on me, and I was forced to flee.