Where do you get the secret potion in Oliver town?

It sounds like you're referring to a fictional town or game! I don't have any information about a "secret potion" in a place called "Oliver Town."

To help me understand what you're asking, please tell me:

* What game or story is this from? (Is it a video game, a book, a movie, etc.?)

* What is the secret potion used for?

* Are there any other details about the potion or how to obtain it?

The more information you give me, the better I can help! 😊