u/malabar1234

The Akatsuki no Requiem ending was always the true ending—and always will be.
It resolves an astounding number of narrative elements.
The lie at the beginning of the story becomes the truth at the end:
“Humanity outside the walls has been wiped out by Titans. We are the only survivors.”
Even Paradis’ symbolism and its mythological figure find new meaning.
Eren becomes the Devil of All Earth because he flattens the entire world, leaving only “heaven” safe.
Eren’s character arc comes full circle:
Trampled Home → Restored Home.
Stolen Mother → Protected Daughter.
“To You, 2000 Years From Now” finds a new emotional meaning: Father to Daughter.
Eren Yeager & Ymir Fritz/Yeager.
“Because I was born into this world.”
Freedom at birth lifts the Titan Curse:
Titan ≠ Baby.
Is it normal for this many themes to converge so perfectly?
Can that really happen “by accident”?
Just from theorizing around a music video?

This theory is a serious attempt to reconstruct what Armin Arlert’s original conclusion could have looked like.
This was crafted through analysis of the manga, through the lens of the Akatsuki no Requiem theory and official material such as the anime’s openings.
Attack on Titan separates its central characters through different pursuits : Truth, Beauty, and Freedom.
At the center of this structure lies the relationship between Armin Arlert and Eren Yeager.
The core of this essay revolves around their dynamic and is built primarily on narrative reciprocity and symbolic convergence.

“Me… if I could understand WHY I had to die..”

My theory: Armin dies at the lifting of the Titan curse 
The theory assumes AnR’s premises: 
- Eren being the father of Historia’s child.
- A completed rumbling
- Ymir’s rebirth
- The lifting of the Titan curse

Pre timeskip
Armin’s nature: Curiosity and wonder.
His dream: The sea. The world.
Eren’s nature: refusal of cages.
His dream: Unrevealed.
Eren hates oppression. He wants freedom.
He desires a free world; a world without cages
They pursue different things, but both paths lead outside the walls.
Armin awoke Eren to the existence of cages and began Eren’s refusal of them.
Armin believes Eren is moved by the world just like him, he believes they share the same dream.
They do not.
Armin doesn’t understand what Eren truly seeks. 

A second life through Titan power. 
Before Return to Shiganshina, it is important to establish that Attack on Titan has already associated Titan power with the gift of a second life.
The blueprint is Freckled Ymir. 
After dying, Ymir wanders for decades as a pure Titan outside the walls. When she consumes a Titan shifter and regains Human form, she repeatedly describes the experience as a second chance; A whole new life.
It’s a rebirth through Titan power.
Ymir receives a new life after her original death. Titan power grants her another existence.
The story itself establishes a connection between Titan power and rebirth.
This becomes important later because Ymir is not the only character whose life reaches its end and is returned through Titan power…

Return to Shiganshina: Dreams and Sacrifice. 
Erwin’s dream: The truth. The basement.
Erwin’s truth lies beneath Eren’s home.
“I’ll never learn what’s in that basement”
Erwin gives up on his dream and dies leading the charge against the Beast Titan, giving Levi an opening.
Armin’s dream: The sea. The world
“I’ll never be able to reach the sea”
Armin gives up on his dream and dies burning against the Colossal Titan, giving Eren an opening.
As Armin falls he says;
“I entrust my life and my dream to Eren.”
“He’ll reach the sea for me”
It isn’t symbolic. It becomes literal.
Armin’s life and dream have been given to Eren.
Both Erwin and Armin abandoned their dreams.
Both abandoned their lives.

 Serumbowl: The Crossroad of Dreams
 Erwin or Armin? Which dream will live?
Both are on the brink of death and only one can be saved.
Levi’s decision is clear: Erwin gets the injection.
Eren argues for Armin with logic and utility.
Floch introduces the role of The Devil while arguing for Erwin
“The Devil himself is the only one who can destroy the Titans.”
Eren stops arguing about strategy.
He talks about the sea. About Armin’s dream.
It’s a purely emotional attempt to save Armin.
Ultimately, because of Eren’s efforts Levi decides Armin will live.
Erwin dies.
Erwin never reaches the basement. He never discovers the truth.
Armin is revived.
Armin inherits the colossal Titan.
Without Eren, Armin dies.
The established outcome was Erwin’s survival.
Eren’s refusal of Armin’s death disrupts that outcome.
Therefore Armin’s second life is inseparable from Eren’s intervention.
His new existence is caused by two facts:
-Eren chose to give him another life.
-Eren chose to preserve his dream.
Armin acquires a second chance after his original death.
Through Titan power. Like Freckled Ymir.
A rebirth.
Armin was saved.
Erwin dies.
And yet, the Devil is still inherited. And so is his dream…

The sea 
Armin reaches the sea himself.
Eren witnesses Armin achieve the dream he originally sacrificed.
Armin is fulfilled while Eren looks ahead.
There’s still things denying freedom.
Eren’s dream isn’t achieved yet. 
That scene fully displays the difference between Eren and Armin.
The tragedy begins; the world becomes the cage.
The world clashes with freedom.
Armin gave Eren his life and dream.
Eren preserved both.
Eren resurrected Armin.
Armin achieved his dream at the sea.
Eren witnessed it.
The dream has been fulfilled.
What about the life now?
What purpose remains for Armin’s second life?
Will his borrowed life be taken back? If so, when?
More importantly, what is the meaning of his death?
Armin needs to understand it.
So what is there for him to understand in this second life?
What truth is there for him to uncover?
The man responsible for his Rebirth.

Post Timeskip 
Floch followed Erwin Smith until his death because he believed only the Devil could destroy the Titans.
Floch follows Eren Yeager and calls him The Devil.
For the very first time Armin thinks he doesn’t understand Eren anymore.
Eren has started the rumbling to achieve freedom and destroy the last cage—the world.

AnR 
As the logical continuation of his belief in birth,
Eren Yeager is revealed to be the father of Historia's child. 
Eren confronts the alliance and believes in himself.
  The alliance fails to stop Eren and most die during the battle. 
All the world’s homes have been trampled
The Titans of the Walls have marched to the end of their function.
Freedom is achieved. The cages have been destroyed.
And yet Eren keeps moving forward.
Eren destroyed the cage;he destroyed the world.
So why was freedom even important? What is Eren’s destination?

The final stage: Post rumbling
Eren returns to Paradis and retrieves Armin with him.
At this point, the theory introduces its main speculative hinge: Armin is fatally injured. He is agonizing.
This is not derived from a specific narrative structure or recurring motif. Rather, it is an inference introduced because it creates a direct parallel to a previous narrative event.
He is at death's door, yet he’s still breathing.
Armin’s body has reached a point where it can no longer sustain itself without Titan power. 
Titan power is no longer merely healing him; it is the reason he is still alive.
This mirrors Midnight Sun: Armin’s body is once again at the edge of death with Titan power determining his survival.
Except this time Armin:
•     Reached The sea 
•     Has watched the world he wanted to see rumbled by Eren  
And yet; He doesn’t understand what Eren is trying to reach. 

The Devil’s Dream: The Lifting of the Titan Curse.
Eren finally reaches home
Eren holds his and Historia Reiss’s child.
“You are free.”
— Eren to Ymir.
This is what Eren was moving toward all along.
Home.
Armin witnesses it.
Eren’s dream is reclaimed: A home in a free world
A place where those he loves can exist without confinement, threats or oppression.
Armin finally realizes:
He and Eren never shared the same dream.
The Titan Curse disappears with Ymir’s Rebirth.
With Ymir finally free, her bondage vanishes :
• Titan powers,
• Paths,
•     & Ymir’s Curse. 
Armin witnesses:
• Eren’s dream,
• The end of the Titan era.
Ymir is reborn. The Titan era ends.
The Devil’s purpose is complete.

At the same time, another rebirth ends.
Armin’s.
As the Titan Curse disappears, the mechanism sustaining his life fades away.
His regeneration stops.
The entirety of the Titans fall.
The Wall Titans of the Rumbling; but not only :
Armin too. 
All Colossals must fall that day. 
The First Colossal destroyed Eren’s home as a son, with the debris of the Walls.
The Last Colossal witnesses the return of Eren’s home as a father, in a World without Walls.
The final truth Armin learns is what Eren’s dream truly was: Home.

 Armin understands with his last breath. 

What this theory concludes:

The Dreams 
Erwin’s dream: Truth
Lies in Grisha’s books.
The sacrificed dream: In the basement, under Eren’s home.
Armin’s dream: The World
Through: Wonder and curiosity
Freedom found in a seashell.
Achieved at the sea.
Eren’s dream: Home
Through: The destruction of cages
Freedom born into this world in a baby.
Achieved at Ymir’s birth.
Armin seeks the world. Eren seeks home.
The two friends get to hold their dreams; one with a seashell and the other with a newborn.
The accomplishment of the second destroys the first.
The tragedy is: two beautiful but incompatible dreams.
The role of the Devil might’ve been inherited by Eren, but Erwin’s pursuit of truth has been inherited by Armin who discovers it not beneath Eren’s home,but within it.
 
The Life Debt
Armin’s death is the closing of a structure that began at Shiganshina:
• He entrusted his life and his dream to Eren.
• Eren forcibly granted Armin a second life over Erwin’s.
  Armin’s rebirth is caused by Eren.
Eren compels Armin to fulfill the dream he had sacrificed.
  Eren witnessed Armin achieving his dream at the sea ; Armin’s rebirth reaches completion when he witnesses Eren achieving his dream at home.

 Eren’s dream ultimately brings Armin’s death, as its fulfillment erases titan power and the force sustaining Armin’s body.
Armin’s death is the beginning of Grief for Eren;
Armin’s body is the only one Eren recovers and buries. The first grave in a field filled with them.
The grave exists because Home returned.

The reciprocity of Armin’s deaths:
  The injured Armin is revived by Titan power through rebirth
  Then, the injured Armin is ended by lack of Titan power through rebirth in Ymir.
Eren Yeager is responsible for both events. 
The achievement of Eren’s dream ends Armin’s rebirth.

Rebirths:
Freckled Ymir = reborn through Titan power
Armin Arlert = reborn through Titan power
Founder Ymir = reborn through birth
Armin’s rebirth lasts up to Ymir’s rebirth.
The reborn Armin witnesses Ymir being reborn and the lifting of the titan curse.

This theory of Armin’s death concludes all these threads:
-The Dreams,
-The Life debt,
-The Colossals,
-The Devil,
-The Rebirth,
-Truth.

They all converge at a single moment: 

The Lifting of the Titan Curse.