Everything that happened to Present Zamasu happened to Goku Black before Goku Black became a thing. Remember, because of Beerus killing Zamasu, the timeline split into two. Everything that happened prior to Beerus killing Zamasu, happened in another timeline with another version of Zamasu. So Present Zamasu's descent into darkness is actually identical to that of the Zamasu from the split timeline who used the Super Dragon Ball to become Goku Black. Hell, Goku Black even specifically mentions in the anime of his humiliation of being defeated by Goku.fadeddreams5 wrote:The Joker is a special type of crazy, and his exact origin isn't really known. There's multiple, IIRC.Lord Beerus wrote:There's no specific time-frame for which a character can lose their rational thinking and go off the deep end. The Joker lost his sanity in the span of one day. All the incarnations of Zamasu, Present Zamasu, Future Zamasu, Goku Black and Merged Zamasu represent different stages of Zamasu's character as whole. You see the young, bashful and down-to-earth Kaioshin who ultimately calls a spade a spade and knows of just how dangerous mortals can be and openly questions the system that he is a part of and became jaded and disillusioned by what he saw and what he knew. Then Goku Black and Future Zamasu provide the next stage of Zamasu's development by embodying the now much more deep rooted hatred for mortals, with him relishing in their destruction. Merged Zamasu is the culmination of Zamasu's character arc. He eventually morally degraded so much that what he became what he set out to destroy for a sake of what he though would be a better universe. I think Zamasu had a good amount of development for the time the Future Trunks arc lasted.fadeddreams5 wrote:^ That was a good description of the character, but it's also an example as to why he's a terribly written one. Rather, he had the potential to be well-written based on everything you wrote, but the execution made him fall short of this. Zamasu is the sort of villain that needed to be fleshed out and developed a lot more. Like, they could have introduced him as a spectator at the Champa tournament prior to this. Reason being, all the events that transpired happened within days. DAYS. And all of a sudden, he snaps. But before any of this occurred, everyone was already deducing that Zamasu was Black due to his constant glares and questioning of humanity the minute he was introduced. Remember, this is a Kaioshin; he's been alive for thousands of years and was stated to be a Kaio prior to this occupation, so him quickly going batshit insane just didn't feel believable or natural. He seemed like your average run of the mill villain, as opposed to someone who actually cared about his universe. Add to the fact that he's later seen destroying and burning the world while praising its collapse/beauty. In the case of Black, this is fine, as the saiyan genes could have been stated to corrupt his mindset, but they continued to display Zamasu as a diabolical villain as well. Was the hypocrisy deliberate? Very likely, but it did not help Zamasu's character at all. Well, in the sense of being empathetic with him, anyways.
He was a poor man's Aizen. A character created to be seen as more "complex" than other DB villains, but this was all smokes and mirrors. Zamasu is as basic as they come-- no different from Vaccine Man from the first episode of One Punch Man.
I wouldn't call the other incarnations of Zamasu "stages" of the character because he never grows into them, if that makes sense. He sort of just became Black, and the saiyan genes clearly had some influence on his actions. Future Zamasu is actually proof that Zamasu was always a douche. Think about it: this Zamasu experienced exactly the same things as present Zamasu, minus his interactions with Goku, and lived for over a decade longer, but he remained a servant to Gowasu. Zamasu was always seeking a way to break free and kill people, and Goku was that answer. The catalyst. This character underwent almost no development. He simply hated humans for the sake of hating them.
You could argue Zamasu loved the universe, the lesser creatures that inhabit it, and all the creations of the gods, minus humans, but this is never really explored at all outside the manga. All we get is he hates humans. There's no drive besides the fact that they destroy shit, so he fixes this issues by destroying more shit.
What they did was actually really clever. You thought after witnessing Present Zamasu's fall from grace that Goku Black's background was more shallow and he was just a case of being evil for the sake of it. But he went through the exact same thing as Present Zamaus. Visiting Planet Babarian, getting humbled by SSJ2 Goku, his hatred for mortal intensifying as a result and wanting to kill Gowasu and steal his time ring. Present Zamasu's backstory was also Goku Black's backstory. The only difference between Present Zamasu and Goku Black was that nobody was around to stop Goku Black from happening in the split timeline.
That why I same the different incarnations of Zamasu represent different stages of his character development. You see his fall from grace with Present Zamasu. Then Goku Black embodies the next stage of his development as you witness what happened if he went through the exact same scenario that Present Zamasu did but nobody was around to stop him from going full blown misanthrope. Future Zamasu is a representation of Zamasu basically embracing his resentment for mortals, through the literal manifestation of Goku Black, much like making a deal with the devil, and deciding to make a difference.