5. Barty Crouch Jr.
I will admit, being sent to Azkaban before your twentieth birthday by your own father would fill even the purest wizard with rage, but given the influential and highly respected family he comes from, Bartemius “Barty” Crouch Jr. has no excuse for the crimes that earned him his conviction, which he committed when he was only a teen.
Worst acts and attributes: The sworn Death Eater is also a skilled actor, as he proved from his impersonation of Alastor “Madeye” Moody with help from Polyjuice Potion, allowing him to enter Harry Potter’s name in the Goblet of Fire and, as a result, play a crucial role in Voldemort’s resurrection and, indirectly, Cedric Diggory’s murder.
Level of Terribleness: 8/10