...I´ve just realized that Shinnok hasn't any special moves, he is only able to use oter fighters' attacks. Do you people think he will only reproduce attacks once more or Midway will create special moves for Shinnok?
Doubtful. That would make for 2 Shujinkos basically. Most likely we'll see a set of moves for Shinnok that are not necesarrily unique (possibly a combination of older special moves from other characters that they don't use any more, like Quan-Chi's stomp and a few others).
Shinnok had a wealth of sweet moves in MKM:SZ that they just left out of MK4...it was terrible. He had purple fireballs as well as a beam attack and a force-shield, not to mention he could morph into a monstrous bug-like being. (can you say Animality anyone?)
Shinnok is a fallen elder God who tried to take the Earth Realm millions of years before MK1. Raiden (then supposedlly quite young as a God) beat him. Don't ask how, he just did. And banished him too.