Goku Black should have been his own character

[thegamer23]

He may have been just a fake at the beginning. Just a Zamasu in Goku's body, nothing more, nothing less.

But each battle forged him, living in human's shoes changed his personality, going on a different level from the Zamasu we know.
Zamasu only cares about immortality while Black adopted some of Goku's personality traits.

He loves fighting, he loves to prove his powers against strong opponents, and he just doesn't care about being immortal.

At this point, i consider him as a unique carachter. A shame he's going to fuse next episode, as we probably won't see Black anymore

[KingKaash]

When the arc started, it looked Goku Black was the main villain and Zamasu was just going to be a side character and maybe even a character that was once good that became evil but still could be salvaged and return to being a good guy. Now we find out that Zamasu is the true villain and Black is kind of a sidekick to him. I still like the concept of it being Present Zamasu though, especially after they portrayed the flashbacks of him using the Super Dragon Balls to take the body. It shows that the right guy can take Goku's body and do wonderous (evil) things with it. Whereas a dimwit like Ginyu can take Goku's body and not even know the depths of its power and how to use it.

[Retan]

Was it ever explained why Goku Blacks power is alway rising?

[Cipher]

Was it ever explained why Goku Blacks power is alway rising?

Not really. Just some combination of standard Saiyan post-battle power-ups and Zamasu getting used to functioning in Goku's body.

Presumably even though he wound up quite a bit more powerful than Goku and Vegeta, he didn't do anything wildly outside the realms of their own potential, as proven by Vegeta getting the upper hand on him last episode.

He also probably "works" a little differently than them, due to Zamasu's ki, which is evidenced by the Rosé form if nothing else.

[Jinzoningen MULE]

Was it ever explained why Goku Blacks power is alway rising?

He often attributes it to his Saiyan body, so it's probably an inconsistent implementation of Zenkai.

[DragonHermit]

Maybe that Universe 12 guy who first time travelled is somehow involved.

That was manga only.

I doubt it's manga only. It's just the manga mentioned it first just like they did with the whole kaioshin/GoD thing. We'll probably hear about the U12 guy in the next arc.