The 'Evil Villan' of the whole plotline, should be able to sound like a normal yet strict headmaster and an evil howling spirit which should be fun. Ghost's don't scream so I'll just wright another ghostly attack line for line three. For the ghost lines firstly, feel free to add any modulation you like (or not, don't mind either way), but the main thing is lines that play while we wonders randomly arround the school, so not an emidient angry chacing threat but more like random mumbles, still give the lines alot of enthusiasm. But not angry as such, more like demanding and strict. Good luck!