i very much doubt hes playable without using a cheat or somethin

Pshhhh if he WAS playable I wouldn't use him because he would be very cheesey but I might play as him for funn who knows.

from what i hear....he WAS playable but they took him out....it would of been mk4 all over again...i hated being shinok and knowing he was the last boss!

Yes he is playable. I got him and i also got Akuma.
To get akuma you must beat konquest and get everyitem and do every mission.
Then go talk to Kai who will say (do this after you kill Shao Kahn with Raidens Staff)
"I have entered into a new Mortal Kombat but I was beatn by the Master of Fists, if you want to try and beat him go to Chaos, he is waiting for a new Challenger"
NEW MISSION: Go Beat Akuma
Go to Chaos and Akuma is in D-7 go and talk to him and he immediatly fights you.
Beat him and he is playable.
However he is super tough, the settings for the fight are
He does 500% damage, he heals, you do 10% damage and your bleeding and you have to beat him in 15 seconds.
Go luck and enjoy the master of fists.

I bet it is in the dark too.

****** SPOILERS ******
And if you play arcade mode with Akuma, the final boss isn't the Dragon King... because after beat him, appears the "nemesis" of Akuma... Devil Ogre Heihachi... and in his ending, we can see the fight between Akuma and Devil Ogre Heihachi after Akuma killed Onaga... and a explosion slays both kombatans... in the final pic, we can see the true champion (that he causes the explosion) saying.... "It's me, Mario!"
Note: Kinda funny, obviously fake, like the above user... and Sonic Rulz over Mario!

i think onaga is SOMEHOW unlockable... though i doubt it...
there was a gameshark code to play as moloch, and i know of some ar max codes to replace scorpion with onaga... i just never got around to putting them in (( o)_( o)) shut up tomtaz i've been busy! lmao.
though... i would think he is unlockable since they do have an ending for him (well... ending pictures.... both unlockable in the krypt, dont know the koffins though)