- "This is to certify that you have failed W.O.M.B.A.T. Grade 2 and have been awarded the classification of Troll. Although this was a difficult examination, it was quite an achievement for you to score zero. We are forced to conclude that you were either making a rebellious statement about the futility of formal education (in which case you are probably a member of a subversive goblin group), or that you were too busy attempting to eat the examination paper to notice the questions (in which case, you are a troll)."
- —A letter sent to certify a Troll-graded W.O.M.B.A.T.[src]
Troll is one of the three failing grades, out of six grades overall, in the Ordinary Wizarding Levels, Nastily Exhausting Wizarding Tests, and Wizards' Ordinary Magic and Basic Aptitude Tests. It is the lowest mark, immediately below 'Dreadful'.
It appears to be generally be reserved for those who receive the worst score possible, usually through making an extra effort to fail. There are no known recipients. Some people, including Hermione Granger, did not know it existed, hinting that the grade is seldomly attributed.
Advancing to N.E.W.T.-level
If a student is given a 'Troll' grade on their O.W.L. test, they have failed that subject and are thus unable to continue with that class at a N.E.W.T. level. The same goes for the other two failing grades: 'Poor' and 'Dreadful'.
- There are no known recipients.
Behind the scenes
- The grade "Troll", as the worst of the failing grades, comes from the fact that the Troll species is known to be incredibly dim-witted.
- In LEGO Harry Potter: Years 1-4, Hermione Granger's boggart is Professor McGonagall showing her an essay with a Troll's head on it, obviously meaning a Troll grade. Her Riddikulus is the teacher presenting her an award.
- Harry Potter and the Order of the Phoenix (Mentioned only)
- Harry Potter and the Order of the Phoenix (video game)
- Harry Potter and the Half-Blood Prince (Mentioned only)
- J.K. Rowling's Official Site
- LEGO Harry Potter: Years 1-4