the most easy way is you take the Canvas of the Image/Sprite and save the original Bitmap thing (for restore at end of FX process) and then operate with that Canvas and some functions of “draw” for make things like some star-spots (example of FX) and then at end of FX restore the saved Bitmap state for view normal Card .
NOTE that this works at the inside region of the whole card Sprite….if you want for example the FX makes over and outside the card you could have to use another Sprite/Image onto the card for make realize the FX