You'll need to be on the paid version of ChatGPT to use the image generation feature.
The process involves taking a screenshot and pasting it into ChatGPT with a simple prompt to recreate the style.
ChatGPT can generate a near-perfect replica of the original image, which can then be cleaned and individual assets extracted using tools like Photoshop or Photopea.
The technique has been applied to popular mobile games like the sticker game and Angry Birds.