Honestly I don't think anyone really knows what the genetic limits are with ball pythons. I have been told in the beginning of this morph craze no one know or really believed that the morphs would "stack" at all. So the Bumble Bee was a real shocker. I agree with the previous poster that there will definately be some mutations that when "stacked" will not thrive or survive and some will not readily "stack" because of their location on the chromosomes. Other than those limitations I personally think the sky is the limit.