What Am I Riddles

Question: I'm light as a feather, yet the strongest man can't hold me for more than 5 minutes. What am I?

Question: One evening a man started to run. Then he turned left. Soon after, he turned left again. Then he started running home. When he got home there were 2 masked men waiting for him. Who were they?

Question: It brings light to a dark dark world,
In a current it travels and through tunnels it's hurled.
Touch it and it'll kill you.

What is it?

Question: I am the beginning of the end, the end of every place. I am the beginning of eternity, the end of time and space. What am I?

Question: My shallow hills are the faces of kings.
My horizon is always near.
My music sends men to the grave.
My absence sends men to work.

What am I?