WARNING: The following contains spoilers for Loki Episode 4, "The Nexus Event," now streaming on Disney+.
In Loki, Tom Hiddleston's God of Mischief has accepted his sins of old, shown immense regret and has slowly begun moving down a more heroic path. Admittedly, he's still difficult to trust -- he is a Loki, after all -- and will do anything to survive. However, as the Asgardian trickster embarks on his true redemption, the big catalyst involves a tragedy that proves Owen Wilson's Mobius is indeed better than Odin and Thor when it comes to inspiring Loki to greatness.
Although the Asgardian royals have tried to make Loki better, it's always felt like they just wanted him to do so in order to make their lives more convenient. Their words felt as though they came from a place of duty rather than love, which is why Loki has never found their ways to be genuine, emotional or sentimental. He simply doesn't buy into them, as they were never his friends in the first place, but in contrast, Mobius ticks all the right boxes.
After the Trickster is trapped in a time loop in the latest episode of Loki, Mobius sneaks in to break him out, adamantly telling Loki that he can be anything he wants to be. He makes it clear with this second chance that the God of Mischief can be a true hero, something not even the trickster ever thought possible. As Mobius motivates Loki, it's clear that the Laufeyson is feeling it because Mobius is his friend. He's always preferred that term over "partner," and the thing is, Mobius didn't have to do that.
Throughout Loki, Mobius could have treated Loki like a prisoner, cold and bitter, but he was always warm and caring. Loki understands how much Mobius really likes him and sees his potential, despite all his past misdeeds. This sets the TVA agent apart from his adoptive dad and brother, who just kept him pigeonholed as a black sheep, informing the narratives other people crafted all along.
It's why Loki trusts his friend, but sadly, they meet Ravonna Renslayer and the TVA agents as they bust out. This creates a heartbreaking moment where Renslayer has Mobius pruned, disintegrating before Loki's very eyes. The agony is plain on Loki's face as his eyes tear up, replicating the hurt he felt when he read about the Asgardian death toll in Ragnarok.
He hasn't known true loss until now and this hits home on a real level, the same way the hypothetical death of Frigga did. As he watches his first real friend die, his reaction indicates that Loki's ready for revenge but this time, in the shape of justice. It's why he and Sylvie wreak havoc with Hunter B-15 against Renslayer and the Time Keepers. Loki's now fighting to free the Variants of the TVA in the name of Mobius and ensure all of reality has free will again rather than just an illusion.
Loki stars Tom Hiddleston, Owen Wilson, Gugu Mbatha-Raw, Wunmi Mosaku, Sophia Di Martino, Richard E. Grant, Sasha Lane, and Eugene Cordero. New episodes air Wednesdays on Disney+.