While Dragon Ball Super Future Trunks Saga We meet Zamasu, the Kaioshin apprentice who is to replace the Universe 10 Kaioshin. He, irritated by Goku and angered by human violence, decided to exterminate living beings through a crazy and complex plan.
In order to achieve his "Zero Human" plan, he first takes control of Goku's body through the current timeline's Super Dragon Balls Zamasu, becomes Goku Black, and later merges with Future using the Potara earrings that Kaioshin Gowasu stole Zamasu. In the process, Zamasu Fuso was born, one of the most powerful characters in the entire work. but Who defeated Goku Black?
Despite their Super Saiyan blue, neither Goku nor Vegeta manage to worry the slightest bit Fused Zamasu. However, this fusion reveals the only weak side of the antagonist. While Fused Zamasu's body is immortal as a god, Goku Black is not as he is mortal. This is how the two halves come into conflict in Fused Zamasu, who could even die given the extensive damage.
When Goku and Vegeta discover this, they also carry Potara and join in Vegeta, who manages to fight at eye level with the opponent with the Super Saiyan Blue. However, Vegetto will not be the one to kill Fused Zamasu as the fusion between Goku and Vegeta completely depletes his energy before time runs out. Here we leave you a comparison of the Potara castings of Dragon Ball Super.
At this point it is Future Tribes to take the reins of the fight and manages to stab Fused Zamasu in the chest. But even in this case, the antagonist doesn't actually die, but comes back stronger and more vicious than ever.
It's just Goku's stroke of genius to save the tragic situation. He summons the Zeno of the future and asks the most powerful deity in the entire multiverse to eradicate this menace forever. And so Future Zeno kills Fused Zamasu. We welcome you and let you to a beautiful fanart of Black Goku Super Saiyan Rosé.