Ok, so before you verse Maleficent, make sure you and Donald and Goofy are at a high level and make sure you have a lot of potions and stuff like that if you want to make this battle quick. Then go to the place where you verse the giant dragon and(YOU HAD BETTER HURRY) look around the field. Somewhere there should be a kind of little cave of roots. Lock onto Maleficent and keep pressing triangle nonstop(it makes Donald and Goofy go full force on a locked on person). Now all you need to do is use any type of healing thing to heal you, Donald, or Goofy(also for you because these green fireball thingys can still hit you). Finally, when she has almost nothing left, go and beat the crud outta her. Other than that, you can just relax and tell a brother and/or sister that you're so good at video games that you can actually do nothing and still win. This strategy might take a long time, but would you rather take hours trying to find a way to beat her, or would you rather take a little more than 20 minutes? Trust me on this! It's worked for me. All 17 times(those are the times I've beaten the whole game).