From Dragon Quest Wiki

Defuddle is a spell in the series that cures one ally of confusion.


Dragon Quest XI: Echoes of an Elusive Age

Rab joins the party having already learned the spell, and it costs 2 MP.

Dragon Quest Monsters

Called DeChaos in this game, it requires a monster to reach level 6 with 24 MP and 22 intelligence. It is naturally learned by the CoilBird and EvilWand.

Dragon Quest Monsters 2

DeChaos now requires 40 intelligence to learn.