I thimk the joke characters are necessary. No videogame(not even MK)should take itself too seriously.

In MK4/Gold Noob Saibot had a bio, but no ending it was in a Tip & Tricks Magazine, but I don't remember what it was. Reptile wasn't originally a reptile. In MK1 he was a combination of Sub-Zero and Scorpion so they combined their colors to make green and called him Reptile. In MKII they put the whole Reptilian creature spin onto things, so the unoriginality wasn't in the name, but character development. I don't think Ermac was a joke character, but just something to sooth the fans due to the still heated controversy of whether or not he is in MK1... Mokap is a joke obviously, meat was just the way the character looked, it was just something to make the game last longer and wasn't really a 'character' in my opinion.

You mean this?

"After turning traitor to Shao Kahn - and bringing power to Shinnok in his quest to defeat the elder gods - treachery is all that the dark ninja knows. As a member of the brothers of the shadow, Noob Saibot is bound to protect Shinnok and his minions against the Thunder God, Raiden."

In addition to it not being official, it still doesn't give us any real insight into his personality, or personal aims or goals. All he does is serve and protect.