You try everything you can to break Robbie's spell, but he's a much more skilled wizard that you are--he's had 3 more years of training to start. But you manage to use a simple telekinesis spell to slide the bolt that keeps you in the stall. Just as the bolt slides free, a stable hand appears with a tatoo kit. You back away, and he comments that with all the ghosts and spells floating around the campus, he'll have to padlock all the stalls. He whispers a soothing spell, and you find yourself transfixed by the hand's calming spell. He raises your lip, and rubs anesthetic on your gums, then he tatoos the identification number that Robbie has given him for you.
He chuckles as he tells you that you'll be earning a letter in Polo, something usually reserved for juniors and seniors. He then proceeds to lead you to the blacksmith's shop. You are still entranced by his spell, and calmly raise each hoof as commanded for the iron shoes to be hammered into place. The hand chuckles with the blacksmith as they share the joke that the iron will seal you in equine form. You're so mad that you buck and bite at the two men, but the calming spell soon has you transfixed again.
"I wouldn't try that again bucko, or you may just have to geld you. Oh, and don't say we'd never do that to a student, cause we have. The can grow you a new pair, but they're never quite the same-if you know what I mean."
You nod your head. As the stable hand backs toward the barrel he was sitting on, you levitate an old horseshoe with bent nails sticking out of it from the adjacent barrel to the hand's seat. He let's out a blood-curdling scream and wails into the blacksmith. The smithy insists that the hand pay attention to where he's sitting, and that the shoe was probably there the whole time. You smile inwardly. Your feet may feel weird from the shod hooves and your newly tatooed gum are starting to ache, but the stable hand won't be able to sit comfortably for weeks, and the blacksmith will have a black eye for nearly as long.
Now how to get even with Robbie? you contemplate your vengeance as the handler passes you off to another stable hand, and heads toward the infirmary.