Demon Magician

The Demon Magician was a malevolent entity who used his magic to interefere with Santa Claus's toy making. He tried to stop the the First Doctor, John and Gillian from helping Santa, first by making a huge wall to block their way, then by animating a snowman to attack them. After escaping from both traps, they defeated the Demon Magician by shrinking him with the Doctor's model-making machine, then trapping him in a toy rocket which they launched. (TVC: A Christmas Story)