Cilla very timidly made her way to the front of the class. "Hello. My name's Cilla Ashcroft and I'm a Third Year Slytherin. I am going to teach you the Shield Charm which is useful in protecting against spells and weapons such as centaur arrows. However, it won't protect against the Killing Curse"

She raised her wand. "The wand movement is a simple vertical slash motion like so..." Cilla moved her wand in a quick vertical slash. "The incantation is 'Protego' which is pronounced 'pro-TAY-goh'."

Cilla then turned to face Professor Flamsteed and inhaled. She performed the wand movement she had just taught her fellow students as she said "Protego!" Hopefully, it would protect her against any spells that Flamsteed cast at her.