I assume you haven't played Portable Ops then. There are two conversations that hints as to Zero becoming a major villain.
First this conversation between Ocelot and Gene (the game's antagonist):
Quote:
Originally Posted by Gene (on the phone)
It's me. Somehow I knew it would be you. ...Yes,
negotiations with the Kremlin were a success. They won't interfere with
what's about to happen. I must thank you for all your help. When they
saw the trajectory data for Metal Gear, they knew that this was no
bluff. The CIA must be in a state of total panic about now. All part of
your plan, I presume? Tell me something, though... You couldn't possibly
have obtained the data on your own, could you? There must be someone
backing you. Who is it? Never mind...I've got a fairly good idea who it
is. The man with the same codename as Null... But you do realize you're
betraying you're employer, don't you? Just what is it you've got in
mind? You're not using me, are you? No matter. We'll meet again... in a
new world, one of my own creation. Until then, my friend... Ocelot.
And then we have this post-credit conversation between Ocelot and mysterious person:
Quote:
Originally Posted by Ocelot
Ocelot: Well, I'll be damned. So it was you who was feeding me
information. (pause) Yes, the DCI's death should pass as suicide.
They'll claim he did it because he felt responsible for the theft of
Metal Gear. We can look forward to a major shake-up on the seventh
floor at Langley shortly. It looks as if everything is going exactly
the way you wanted it. (pause) When the DCI saw the trajectory data you
supplied and found out that he was the target of the nuclear strike, he
brought the Philosophers' documents right to me. (pause) Yes, we should
have known Gene was serious about launching those nukes... Seems our
insurance policy came in handy after all. He did quite well... And now
I've got the Legacy. Is that all part of your script, too? Using him
and the FOX Unit like that... Only you could have pulled it off. But... You
won't be using me anymore... (pause) ...Battle data... ...from the Perfect
Soldier? (pause) Genes... genome... (pause) ...I see... Intriguing... I'll help
you with the project. But on one condition... I want him to join us.
(pause) Yes, Big Boss... So that we can become the Patriots.
So the person Gene mentions and the person Ocelot is speaking too is obviously the same person. And going by Gene's hint that his codename is the same as the character Null's we can figure out exactly who it is. Null is German for Zero, after all. Oh and the final lines in in the above conversation is pretty important too to get the bigger picture.
Sounds reasonable? :wacko: