Well done on your accomplishments!

I have been looking at the various mutations and have discovered a distinct pattern...mutations are random, yes, but the location of the plant makes a big difference to its success. I may have to break down and buy brains, because trying to win them in order to proceed is taking a very long time. I'm working on a success chart...a nine-block grid showing the zombie in the middle, surrounded by the best placement of each plant for the best chance of getting the mutation you want.