Yazidis are Zoroastrian
Yes. Zoroastrian and devil worshippers.
Idea is that God is good and there’s no need to fear God.
But the Devil on the other hand is a bad guy who needs to be appeased.
Check out this from a 50’s Adventure magazine.
http://www.scribd.com/mobile/doc/161086690
At page 8 it starts with the author’s Experience with the Yezidis.
Their own name for themselves is Daasin (plural Dawaaseen), which is taken from the name of an old Nestorian - the Ancient Church of the East - diocese, for many of their beliefs are derived from Christianity. They revere both the Bible and the Koran, but much of their own tradition is oral. Due in part to its secrecy, there have been misunderstandings that the complex Yazidi faith is linked to Zoroastrianism with a light/dark duality and even sun worship. Recent scholarship, however, has shown that although their shrines are often decorated with the sun and that graves point east towards the sunrise, they share many elements with Christianity and Islam.
http://www.bbc.com/news/blogs-magazine-monitor-28686607