How do you randomize Pokemon X and y?

To randomize Pokémon X and Y, you'll need to use a tool like PK3DS, which allows you to modify the game's files. First, extract the game's ROM using a suitable program, then open it with PK3DS. You can customize various elements, such as wild encounters, trainer Pokémon, and items, by selecting the appropriate options in the tool. After making your changes, save the modified ROM and load it onto your emulator or 3DS for a randomized experience.