Despite Ultra Instinct, Goku couldn't do anything against Molo, the brutal antagonist of the new storyline. But after saying goodbye to Galactic Patrol Merus, the Saiyan finally learned how to do it master his ultimate ability.
In order to face the new powerful enemy threatening the universe, Goku and Vegeta had to seek help, a member of the Galactic Patrol, who actually turns out to be angels. Merus limited Molo's art, but eventually it has been eliminated from existence for violating angelic laws.
In the new chapter of Dragon Ball Super Goku is in shock for the sad death of his friend, but still he does not allow himself to be carried away by anger, as happened, for example, for the end of Krillin in the Freeza Saga.
Usually Saiyajins use all of their anger to strengthen their powers, but this time Goku channels his emotions in an alternative way. "Merus may have disappeared, but his will will live in me", Says Goku immediately. Finally, it seems that Kakarot is now able to control the power of the Ultra Perfect Instinct. For Molo, the end seems to have come; The antagonist of Dragon Ball Super is eliminated by Goku.
This event proves that neither anger nor complete calm are the right emotions to master Ultra Instinct. It turned out that was Meru's legacy the perfect fuel for this technology. The angel gave Goku another great lesson in Dragon Ball Super.