The form a Patronus takes in Harry Potter can reveal a lot about the personality of the witch or wizard that summons it. The spell to summon a Patronus, Expecto Patronum, is a complicated and advanced magical technique. It's possible for a Patronus to change over time, and some witches or wizards have a Patronus that reflects their love interest, or even their favorite pet.

In Harry Potter, the Patronus is a powerful spell, but it isnt easy to cast. In fact, some of the most advanced wizards struggle with it. The spell itself requires the caster to visualize their happiest memory, and hold onto it very tightly. This sounds simple, but in practice can be quite difficult. The whole point of a Patronus is to ward off Dementors. Dementors suck the soul and happiness out of a person, so the longer it takes an individual to cast a Patronus,...