A computer implemented system and method for generating a game, such as spot-the-difference are provided. The method includes receiving a user-selected original image and storing the image in memory. From the original image, the method includes automatically generating a pair of images which are visually identical except for a predetermined number of random localized modifications, and providing the pair of images to the user as a game which can be played by spotting differences between the pair of images as a result of the modifications.