Who said "Death is not an ending; it's a transformation."?

This quote is attributed to Agatha Harkness.

Death is not an ending; it's a transformation. - Agatha Harkness

"Death is not an ending; it's a transformation."

Agatha Harkness Death

"Well, hello, dearie."

"The real question is, what are you willing to do to keep what you love?"

"Power isn't given, it's taken."

"I'm not a witch. Well, not a traditional one anyway."

"Death doesn't scare me anymore."

"Death and I are old friends."

"Welcome to my world."

"Death is just the beginning."