Glass to sand

It appears as a blue shield made of water that surrounds half of the user, it turns any glass that passes it into water. If it is meant to turn into water and knock the people behind backwards is not known, this could be because of many reasons or it could be meant to do that.

Albus Dumbledore used it in the Ministry of Magic to protect from Voldemorts glass.

Appearances

 * Harry Potter and the Order of the Phoenix (film)