Jelly-Legs Jinx

The Jelly-Legs Jinx (incantation unknown though the counter curse is assumed to be unjellyfy) is a spell that causes the victim's legs to wobble so that they can no longer stand. The jinx is mentioned in the book Curses and Counter-Curses written by Professor Vindictus Viridian.

Known uses

 * Hermione Granger used this jinx on Harry Potter while he was practising the Shield Charm in preparation for the Third Task of the Triwizard Tournament.
 * Vincent Crabbe was hit with this jinx, in combination with Furnunculus, by Harry and George Weasley, causing little tentacles to sprout all over his face.

Behind the scenes

 * The Jelly-Legs Jinx seems to share some similarities with Tarantallegra, although the effects as described are slightly different.

Appearances

 * Harry Potter and the Philosopher's Stone
 * Harry Potter and the Goblet of Fire
 * Harry Potter and the Half-Blood Prince

Notes and references
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