You need Mojave and Mystic to make a Mystic Potion, or Mojave and Phantom to make a Purple Passion (Both combos are similar looking). That's why I'd recommend getting a Mojave combo male, a Mojave female to breed him to and make BELs, and a Mystic or Phantom female to breed him to to make Mystic Potions or Purple Passions. I'd recommend checking out www.worldofballpythons.com and owal genetics calculator. Owal is really useful for seeing what clutches you can create.

Just make sure to Google the names of sellers you're looking to buy from and you can check out Fauna Board of Inquiry to see if they're listed there.