Chapter 80:
You have Levi preparing for defeat if Erwin doesn’t have a plan, and coming up with his own plan.
Levi’s plan of getting Erwin to safety by escaping on Eren, and using the recruits, and Hange’s squad as bait while they too tried to escape, whilst he went after the beast titan so that Erwin could get away.
Levi saying that the recruits, and Hange and their squad will try to escape, and act as bait so that Erwin can escape on Eren’s titan whilst he deals with the beast titan, and Erwin knows that Levi will probably get hurt, or end up dead.
Levi then questions if Erwin has a plan, and when he says yes, it honselty looks like Erwin is lying, and is thinking of something on the spot that would mean that Levi’s survival is guaranteed.
And Erwin’s plan is literally Levi’s plan just with Erwin sacrificing himself by distracting the beast titan’s attention with a suicide charge so that Levi can sneak up on Zeke.
So Erwin’s plan is basically the same as Levi’s, but with the guarantee that Levi will live instead of him.
And Erwin’s willing to give up on his dreams of seeing the basement so that he can lead to recruits to their deaths, just so that Levi’s chance of surviving increases.
He’s really willing to sacrifice himslef and most of the survey corps to protect Levi’s life.
And even though he really wanted to see the basement, to see if his father was right, Levi is clearly much more important to him. Even though they’re so close to the truth, he’s prepared to give that up for Levi’s survival.
Erwin looks to Levi for guidance, and he looks so defeated, that levi takes charge, reassures Erwin that he’s done amazingly, that he’s proud of him, and how far they’ve come because of him.
He tells Erwin to give up on his dreams and die, that he’ll carry out the plan, even though Levi’s expression is so pained, he’s saying it for Erwin, becuase Erwin needs to hear it.
And it’s hinted that Levi is telling Erwin that he’ll carry on his dream, and see it through to the end.
Levi lives by Erwin's words. That to him, taking down the beast titan is the way to give Erwin's life meaning. That him fulfilling their dream would help him think Erwin is resting peacefully.
Erwin trusted Levi with his dreams and goals, and to act in his place. Levi fulfilled every vow he made to Erwin, fought to do so. He found out what was in the basement, took out the beast titan, for Erwin. To ensure that Erwin's death and life had meaning. Levi lived for Erwin.
That everything he does, he does for Erwin. The amount of devotion and dedication Levi had for Erwin, the amount of love is an unstoppable force. Levi isn't going to stop until he has fulfilled the vow, just shows the power of their love.
As Erwin said, it's the living that gives meaning to their comrades lives, and Levi takes it upon himself to prove that Erwin's life had meaning. Fighting to fulfill his promise to Erwin, to see Erwin can rest peacefully now.
