You can never master every form. Or any form, at least fully. As soon as you think you've reached the top, the clouds clear and a vast expanse of learning looms above you. When you think you've seen it all, something new crops up. This is a mighty lofty goal for anyone, considering the relatively short lifespan of the human body.
All things are possible to those who believe. All it really takes is a little will power and you can do anything. Look at jesus...he could do anything he wanted, btw NO I DO NOT THINK JESUS IS THE SUN OF GOD...but imagine being told you were the son of god all your life...imagine the power of feeling like that with no self doubt at all.
I personally think people take the "all things are possible" a little too literally. If you're trying to master all forms in one lifetime then I can say without a doubt, no. But it doesn't mean you shouldn't try. One should never stop trying to learn.