The green menu in Granny Scared 3 is a hidden menu, which players can use in specific occasions to get some special functions. The following are the functions of the built-in menu of Green:

1. Long-distance jump: It allows the protagonist to jump long distances on the map, which is convenient for exploring the map.

2. Run fast: it can make the protagonist move quickly and escape the pursuit of the horrible grandmother.

3. Invisible mode: The protagonist can be invisible in the game, which is convenient for sneaking into the house to collect items.

4. Lock mode: You can temporarily lock the game to prevent being attacked by a scary grandmother.

5. The maps are all open: you can open all the maps in the game, which is convenient for the protagonist to find the exit.

To enter the green built-in menu, players need to collect enough menu fragments in the game and piece them together. Once pieced together, players can use Green's built-in menu in the game.