Harry Potter: 10 Most Powerful Slytherin Students

Looks like the Lestrange family is back at it again, and this time, it's in a far more terrifying package. This witch may have started life as a Black and married into the Lestrange name, but she embodies it perfectly.

Bellatrix takes everything from the Barty Crouch Jr. entry and pushes it to eleven, as she's a pure embodiment of the chaotic/unpredictable nature of dark magic. This former Slytherin student is a terrifying, sadistic and - for want of a better word - crazy person with no remorse for her actions.

Bellatrix is shown to have overwhelming magical strength, as she can destroy things and hurt people with barely the flick of her wand. Still, despite her seemingly tenuous grip on sanity, she is shown to be precise and dangerous with her magic, implying a scary amount of control over it.

Of course, Bellatrix also has one hell of a body count, with her worst victim being the beloved Sirius Black. She's got plenty of blood on her hands, which is why she played such a vital role in Voldemort's evil schemes.