After Dragon Ball Super ended with episode 49, Black Goku found a way to the current time to pick a fight with the real Goku. It was their first fight ever.
But before the fight happens, Black Goku has a special ring and it is an interesting subject. The ring itself enables him to travel through time. In this episode, Black Goku knows who the real Goku is. In the Future Trunks time stream, Goku and Vegeta are dead. Black Goku knows Veerus and Vegeta. This signifies that Black Goku is from a different time stream or time period.
According to Attack of the Fan Boy, Trunks is interested in fighting him but according to Vegeta, he is not strong enough to battle it out. The real Goku then proceeds to confront the impostor.
Black Goku made it known that it is an honor to fight against him inside the body is representing. That sheds a theory that he may not be the Goku, whether black or not, inside that body. It could be another type of character altogether that steals bodies. Past the introductions, the two proceeded to fight. The two seem to be evenly matched in the battle.
Goku loves to test out his opponents first. Which is why he does not go all out. He wants to figure out his enemy first and plus the fact the he loves to fight. He maintains his Super Saiyan 2 form but Future Trunks knows that it is a tricky situation. He knows Goku can upgrade to Super Saiyan 3 or even Super Saiyan Blue. But Black Goku is able to upgrade to dark colors instead of the usual bright light.
What Goku does not know is that Black Goku gets stronger, the longer he fights. Ultimately, Goku weakens him in the abdomen area. It prompted a time shift which pushes Black Goku to a weakened state. In the hustle, he tips over the Time Machine. Eventually he escapes into a time portal. Knowing full well that he is unable to defeat the real Goku.
This fight revealed so much for the Future Trunks saga. Do you think Black Goku will defeat the real Goku anytime soon?
According to the fan wiki, this episode was directed by Morio Hatano who started his work on episode 33 with character designs by Tadayoshi Yamamuro, and story line by Akira Toriyama.