Majin
Use the following trick to acquire the purchasable Majin without repeat the whole game over. Create two saved games of the files you have the Majin you want to take PP, Skill or Sell. Go to the woman that extracts them for you. Once done, save to one of your two saved files. Load the second saved game file. The Majin you extracted will be back in your list and it will have recorded what you did with the previous save. For example, extract PP from a Zerda (level 19 green Velox), save the game, load your backup save, and it will be recorded on the list. Keep doing this until the Majin you have are now purchasable. This works great for Bosses.