How do you get 5th emerald in sonic sex change game?

In the Sonic fan game "Sonic Sex Change," the 5th emerald can be obtained by completing the special stage located in the 5th zone of the game. To access the special stage, you typically need to collect a certain number of rings in the regular levels. Once in the special stage, you must navigate through the obstacles and collect the emerald within the time limit to successfully obtain it. Be sure to utilize Sonic's abilities effectively to reach the emerald and advance in the game.