What happens when you use a Golden Rune?

Could you please elaborate on what precisely occurs when one utilizes a Golden Rune? I'm curious about the specific effects it brings about, whether it's an instantaneous change or a gradual process. Also, does it involve any risks or specific requirements? How does it interact with other elements of the game or system? Would you mind sharing some insights into its unique properties and how it differs from other similar items? Thank you for your time and assistance in answering these questions.