Fast Fly = Combing into flying and following up the fly with an attack (Launch, sj.LP, sj.LP, fly, u+LK, sj.LP, Rocket Punch), this is accomplished by tapping any upward direction WHILE attacking.
UnFly = Being allowed another action (Blocking, Normal Attack, Special Move, Super Move, or calling an assist) after unflying. This is accomplished most commonly by flying with Sentinel and then getting hit by anything that will not land him on his back after it hits. For example, getting hit by any AA = yes, you will get UnFly, BUT, getting hit by flying screen Fierce/RH = no, you won’t get it.
Actually getting hit with a fierce or roundhouse gives you unfly.
An example of getting unfly mode with Sent is to switch characters. When he comes in hit him with a standink lk. He’ll kinda somersault backwards and he’ll be in unfly.
I said FLYING SCREEN Fierce/RH the ones that knock you on your back. And getting UnFly by switching in and hoping that they’ll do a s.Short or something is pretty stupid.