The Boggart-Banishing Spell (Riddikulus) is a charm that is used in defence against a Boggart. It causes the creature to assume a form that is humorous to the caster, along with a whip-crack noise, thereby counteracting the Boggart's ability to terrorise. Boggarts are defeated by laughter, so forcing them to assume an amusing form is the first step to defeating them. However, because Boggarts are amortal, this spell does not truly dispel them, similar to the Patronus Charm.