WARNING: The following contains spoilers for Episode 130 of Dragon Ball Super, "The Greatest Showdown of All Time! The Ultimate Survival Battle!" which debuted Saturday on Adult Swim.
Ever since his introduction at the start of the Tournament of Power, Jiren has largely been depicted as a silent, stoic warrior, with his own sense of honor and nobility amongst the other fighters from across the Dragon Ball Multiverse. Initially a bit of a mystery because of his withdrawn nature, the Universe 11 Pride Trooper quickly established himself as the strongest combatant once he stopped meditating and began to actively play a role in the martial arts competition for the fate of all existence. However, as the last battle in the series intensifies, Jiren, more desperate than he has ever been in his entire life, takes a full heel turn that shows a dark, villainous side to Dragon Ball Super's final antagonist.
Picking up from the cliffhanger ending of the previous episode, Goku has fully mastered his Ultra Instinct transformation, able to completely take advantage of his new state's awesome combat abilities to begin to overpower Jiren. Tapping into the powers of the gods themselves, Goku turns the tide of battle, with Jiren forced not only to tap into his full potential, but push himself beyond his assumed limits just to avoid from being eliminated from the contest of champions. This desperation and strong possibility of defeat leads the normally noble figure to lash out angrily.
Jiren's mysterious background had been revealed towards the end of the series as a young boy whose entire family was eradicated by a powerful villain from his native universe. Trained in martial arts under a strong mentor, the death of his teacher and subsequent abandonment by his friends and fellow students led Jiren to completely swear off the value of friendship and other interpersonal relationships to focus his life entirely on the pursuit of martial arts training and discovering new levels of power; going as far as to pass on an offer to become Universe 11's God of Destruction to continue to dedicate himself to his training.
In sharp contrast, Goku and the Z Fighters from Universe 7 have constantly been driven throughout the Dragon Ball franchise, including the Tournament of Power, to battle on despite overwhelming odds and superior opponents because of their love of family and friends. With the fate of their universe and those living within it at risk of erasure should they lose the competition, the Z Fighters have found new reserves of strength and made numerous, selfless calls to keep their team in the tournament till the very end, with Goku declaring that it is his friends and family that have kept in him the grueling brawl for so long.
Incensed by the very notion that his suddenly stronger opponent draws power from the very thing he had sworn off from his entire life, Jiren launches a massive energy attack at the eliminated Universe 7 team who are spectating the fight from the sidelines in an impulsive effort to punish Goku and demonstrate that friendship is meaningless. Goku is able to cancel out the blast and save the spectators and is visibly infuriated that Jiren would even attempt to so callously destroy them. He then unleashes a powerful barrage of blows that nearly eliminates Jiren for good.
The move to deliberately kill innocents is an unexpected dark turn for Jiren, as someone who had previously kept to his own moral code throughout the competition. However, for the first time since childhood, the Pride Trooper is not only facing someone on equal footing as himself but one that is continually proving to be his superior -- and someone who found greater levels of power through friendship and trust in others. It is a bitter realization for Jiren and, with minutes to spare in the Tournament of Power, leads him to make the single most villainous action in his entire life. And, with Goku's control on Ultra Instinct faltering for maintaining the form for so long, Jiren's true colors will abandon any sense of nobility as he takes advantage of his visibly weakened opponent.
Newly dubbed episodes of Dragon Ball Super air on Saturdays at 11 p.m. ET/PT on Adult Swim.