Once there was a man named Stanley. He was a good craftsman and had a woodcutting factory.
One day he woke up in the nether next to 2 doors. Due to there being a sign saying FORBIDDEN he walked away. A shadow being shot him and he dashed through the left door.

It was a mistake as he fell in a portal that looked like black goo and was never seen again.

10 YEARS LATER

A man named Jimmy was walking to work but collapsed on the sidewalk. 
He later was hospital suffering from a black goo on his arm.

He became a shadow being.
Stanley became a shadow being.

And the cycle continued.