Confundus Charm

The Confundus Charm is a spell with an unknown incantation that causes a person to be confused. The person is affected is to be confunded.

Snape suggested that Harry, Ron, and HErmione were Confunded by Sirius Black into believing him innocent.

Barty Crouch Jr. used this charm to fool the Goblet of Fire into accepting Harry's name under a fourth school.

Hermione used this on Cormac McLaggen during Keeper tryouts for the Gryffindor Quidditch Team.