Igor Karkaroff was a wizard who was a Death Eater until he betrayed some of them in order to avoid Azkaban. After his release he became headmaster of Durmstrang during the 1990s and attended the Triwizard Tournament. During the Third task he went into hiding after hearing that Lord Voldemort had returned to power and did not join the Death Eaters again. In 1996 he got eventually killed by the Death Eaters for his betrayal.
Half- Blood Prince (Game only)
First Wizarding WarEdit
He joined the Death Eaters and befriended Severus Snape and became caught by Mad Eye Moody after helping Antonin Dolohov torture Muggles. He was sent from Azkaban to reveal any Death Eater activity for his release. Igor gave the names Antonin Dolohov, Evan Rosier, Travers, Mulciber, Severus Snape, and Augustus Rookwood but was unsucessful and was sent back to Azkaban.
After his release he became headmaster of Durmstrang during the 1990s and treated his students like they were servants like letting them steer the Durmstrang ship while he stayed at his cabin. The only student he favored was Viktor Krum.
In Harry's Fourth year, he attended the Triwizard Tournament.