The idea is to get out Mrs Norris as fast as you can and deny them of everything. If they do happen to topdeck a creature, during your turn, Cage it and Malfoy it or Blow it up with Incarcifors. When you get the Deny down then Beatdown comes, use cards like Drought of Living Death/Wolf/Mixture to just schlap them in the HEEADD (Inside Joke). Snape is usefull because of the ability to shuffle cards back and he provides Potions. Privit Drive takes care of Potions decks and some Steelclaw decks. Apparate takes care of Reptile House and Unusual Pets wich can be annoying. Try this deck out and I'll be happy to play you on the PoJo HP ladder.