Wow. Why does everyone run to the thorns??? This battle is seriously not horrendously hard.
In advance:
Armor:
Firaga Ring
Firaga Ring
Firaga Ring
You can replace the Firaga Rings with Ribbon or anything that reduces fire damage and highly increases defense. Make sure to get Aeroga from Dalmatians. Well you don't HAVE to, but it's nice to have. Aerora will do okay.
NECESSARY Abilities:
MP Rage, MP Haste, Second Chance
Items:
Elixirs
For Donald, customize his abilities so that he rarely uses defensive, or offensive magic. This way, he'll cure you when you're in need and NOT waste MP on Aeroga. For armor... Fira Rings. Just so he survives longer. For Goofy, customize so he uses Support Action often and everything else rarely. For armor, Fira Rings or any defense. If you don't have enough Fira Rings for both Donald and Goofy, it is better to use on Goofy. Ability for Goofy you MUST equip is MP Gift.
Strategy:
The simplest is do the basic dodging of the tail and fire breathing .But with the setup I made, you can basically tank the battle. Fight the dragon head on. Make sure to have Aeroga on at ALL times. Try not to use Elixirs on yourself, but rather on Goofy when he has no MP. (This way, he can replenish ur MP for you). Summon Tinkerbell (if in normal mode) Cure yourself mostly, and Goofy. Donald can be left alone. Waste of MP. (Sorry Donald!!!) ...ummm...that's about all. The rest is button mashing. It's all about battle prep : ) When you play maleficient the first time, admittedly, you're absolutely unprepared.