Super Dragon Ball: new arc coming this June

The official website of the anime Dragon Ball Super and the tweeter and all the world actually is speaking of the new arc of dragon ball super, starting on 12 June.

A bow on Trunks of the future. Akira Toriyama is concerned with the history and design of the new characters that will appear, including Trunks of the future:

When must of the people are waiting for the hugest tournament ever which means all the 12 galaxy's against each other, The new arc is after the one dedicated to Champa and the tournament between universes 6 and 7. Goku 'and his friends find themselves again Trunks of the future this also a rumor because another rumor is spread in which it is told that turnks will be against a dark goku preaty confusing us you see.

Now the question are Why is he back in this arc as he beat Cell and that peace seemed to get? What is the new enemy? Toriyama hinted that this new adversary be called "Goku Black". A black Goku? He also revealed that the arc would involve both the gods of destruction and the Supreme Kai.