Turns stairs into slides
- "He was on the sixth stair when there was a loud, wailing, klaxon-like sound and the steps melted together to make a long, smooth stone slide like a helter-skelter."
Hermione Granger later performed this spell on an unnamed staircase somewhere at the lower floors in Hogwarts when she, Harry Potter and Ron Weasley were chased there by some Death Eaters during the Battle of Hogwarts.
- Harry Potter and the Order of the Phoenix (First appearance)
- Harry Potter and the Deathly Hallows (First identified as Glisseo)