The Standard Book of Spells
Riddikulus
RIH•DIH•KYOU•LUSS
When fighting against a Boggart (a monster which takes the form of the caster’s greatest fears), Riddikulus forces the Boggart to take the appearance of another object of which the caster is focusing on. These objects are usually a humorous variation of the Boggart, such as a spider on roller-skates or an enemy in laughable clothing.