onyx koin behind chaos realms portal

how do you get the koin that is behind the portal when you enter chaos realm.
You get the coin by pushing an npc to the left side of the portal and keep spamming X to talk to the npc, every time you do this it pushes you back eventually pushing you through the stone fence behind the portal check out a video on YT called mk deception 16 years later the guy shows how to do it.