Scarecrow

From the Super Mario Wiki

Scarecrow is one of the status effects Mario and his crew can be afflicted with in Super Mario RPG: Legend of the Seven Stars. It is caused by enemy attacks such as S'crow Funk and S'crow Bell. While a Scarecrow, Mario and his party can use magic and defend but not attack physically or use items.

[edit] Trivia

• In one scene in The Great Mission to Save Princess Peach, Bowser turns himself into a scarecrow to entertain (and eventually trap) Princess Peach. This scene predated and may have inspired Super Mario RPG's Scarecrow form.
• The effect is also somewhat similar to the Frog status of Final Fantasy games, as it renders the afflicted unable to use certain attacks and transforms him or her.