So far, in my opinion, is one of the best forms I have ever seen. Who can say no to juggle your opponents with never ending combos, unlimited energy, and that oh-so-satisfying-overkilling Mystic Arte? In exchange for all this power, a time limit is set, so use all the power wisely.
The Drive Forms were an excellent addition in Kingdom Hearts 2. With so many forms boosting strength, magic, and speed, each having a unique moveset of its own, it's no wonder these forms are just awesome. Who can deny the awesome, yet flawed Anti-Sora?
A Sonic game really isn't one without the Almighty Super Form. By gather the 7 Chaos Emeralds, Sonic has the power to fly, go super fast, and he's nearly invincible. Just don't forget it has a time limit.