Gus Lanzetta, a brazilian reporter and interviewer for the site IG attended to the E3 this year, and had the chance to actually play the new MK with the game developers.
During his interview with Hector, the exective producer of the game confirmed that this Sub-Zero is the older one, from the first game. So the interviewer asked if the game will have two Zeros, and Hector said "Stop asking me questions that I'm not allowed to answer! If I keep answering, someone will ask me 'Hey, a brazilian site has a lot of information about the game. Is that your fault?' "
Also, Hector said to Gus that Shang Tsung and Raiden will be indeed playable. In another interview, Steve Beran revealed that the Living Forest will have a Stage Fatality.
You can see the entire article (in portuguese) here:
Mortal Kombat volta às origens: Jogamos e conversamos com os produtores | Arena Turbo
(ze maken ook crazy dure, daarmee 
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