User blog comment:EmpyreanSmoke/Supernatural Q&A (Closed)/@comment-27006668-20151110185459/@comment-24834479-20151112220833

1. The mark created a single channel between the bearer and the darkness.

2. Maybe we will find out.

3. I'm honestly not sure about the extent of Cain's abilities. How much power the mark channeled is up for debate.

4. He hasn't his wings, so no.