Shape-shifters that takes on the form of whatever the victim fears most. They thrive in dark, enclosed spaces, and change their appearance on sight. "Riddikulus" is the most effective spell used to destroy a boggart, however, multiple wizards joined together may defeat it more quickly/easily.



Harry Potter - Dementor
Ron Weasley - Acromantula
Hermione Granger - Professor McGonagall telling her she's failed everything.
Neville Longbottom - Severus Snape
Remus Lupin - The full moon
Molly Weasley - The death of her loved ones.
Parvati Patil - A mummy
Seamus Finnigan - A banshee
Dean Thomas - A severed hand moving on its own.
Voldemort - His own corpse (fear of death).
Dumbledore - Corpse of his sister.
J.K. Rowling - Death of loved ones or being buried alive.

Sources: [1] [2] [3]