Apparently he collected the heads...

http://www.dailymail.co.uk/news/article-4170958/Islamic-State-s-chief-executioner-knifed-death-Iraq.html?ito=social-facebook

Islamic State's chief executioner, who has beheaded more than 100 people, has been stabbed to death in an ambush in Iraq.

Nicknamed Abu Sayyaf, he was dubbed one of the terror groups scariest decapitators and was paraded in their sick videos for his huge frame.

He was also said to be leading ISIS in the Nineveh State, where he was killed by an unknown group who swarmed terrorist territory.