Harry Potter is one of the most beloved stories in recent memories. Both the books and movies immerse the audience into a world of witchcraft and wizardry, making us fall in love with the magic, the characters, and just about every aspect there is.
As much as the boy who lived is adored, a story is often only as good as its villain. There had to be someone evil and maniacal enough to put Harry in danger. A big enough obstacle in his way that when he ultimately prevailed it would feel earned and satisfying.
In Lord Voldemort, J.K. Rowling hit a home run, creating a legendary antagonist forever to be remembered as one of the best of the bad guys. However, on his own, Tom Marvolo Riddle couldn't have become the same caliber of big bad he ultimately did. Like Harry needed Dumbledore's army, Voldemort needed his death eaters - unquestioning disciples to do the dark lord's bidding.
There are some that You-Know-Who was right to put his faith in, and others he would come to regret. Those that helped his cause and moved him closer toward his goal of dominion over the wizarding world, and those that were all but passengers on his rise to, and fall from glory.
11. Igor Karkaroff
It wasn't until the Goblet of Fire that the Harry Potter audience was introduced to Igor Karkaroff. The wizard was seemingly nothing more than the Durmstrang Headmaster, until his dark past was uncovered bit by bit, and he was revealed to have been a Death Eater during the first Wizarding War.
After being sent to Azkaban for his crimes, Karkaroff voluntarily confessed the names of Evan Rosier, Augustus Rockwood, Severus Snape, and Barty Crouch Jr. as working for Voldemort in exchange for immediate release. Naturally, this put him on Lord Voldemort's naughty list with a target on his back.
This is why Igor was so concerned in the Goblet of Fire that his dark mark was acting up. Though if he was expecting any help or sympathy from Snape, the man he tried to turn into the authorities, he was looking in completely the wrong place.
One characteristic that any Death Eater needs to become one of the best is loyalty. When Karkaroff betrayed Voldemort to save his own skin, he confirmed his spot at the bottom of this list.