Birth by Sleep A triple help question!?: Dragon Malificent, 3-part Unversed, Unversed Swarm

Terra
Like the Guard Armor from Kingdom Hearts 1, aim for the arms and legs before going for the head. Your shotlock command will really help here since they are big targets, so choose one with a high damage/hit count. Avoid it's attacks by mainly slide dashing away and keep healed when necessary. When the head does the "Rotating giant beam, simply stand directly under it as if you were in the eye of the storm. The multiple laser shots can be deflected with guard. SLEEP won't help you in this battle. Switch it for a good and quick damage dealer.

Ventus
When facing a swarm, it's best to have attacks that will deal damage to multiple enemies (Such as Mine Square or Tornado)
Really, just hit and run, keep yourself healed.

Aqua
Attack the head a few times and do your best to stay behind Maleficent when you need to heal. Pay close attention to Philip when he calls you over to do a powerful reaction command. (Shotlock can help here to) When she is about half health, The dragon will take flight and at this point, go to Philip so he can execute another reaction command that will put you on the flying Maleficent's back. then just hack and slash at her head. If you fall off, just go back to Philip and repeat.