Multiple choice general knowledge who destroyed the horcrux in Rowena Ravenclaw's diadem harry potter albus dumbledore malfoy crabbe Reveal answer Fill a bubble to check yourself D Correct answer Explanation During the Battle of Hogwarts, Vincent Crabbe cast Fiendfyre (cursed fire) in the Room of Requirement, which destroyed Rowena Ravenclaw's diadem horcrux. Though the fire destroyed the horcrux, it also killed Crabbe himself.