A long time ago, a little girl called Ymir changed the world forever; at first, she was only a slave girl to a Tribe called Eldian; just like every other enslaved person at the time, she worked every day and night to secure that she would have something to eat and drink, to survive another day in this cruel world.

What was the point? She didn't know, all her life she had been a slave since she knew anything, she couldn't remember a time where she wasn't one, all her life she did what others ordered her to, mainly her king, King Fritz of Eldia.

Despite living as a slave, she was still kind-hearted; she even helped other slaves whenever she could.

She obeyed every order without resisting or questioning; she was a loyal servant after all, until one night, she was working during the night when her eyes found pigs caged just like her; she knew the fate that sooner or later would come for them.

Due to the kindness of her heart, she released the nine pigs caged; seeing them run away filled her heart with joy. "You're Free," she shouted at the pigs who ran away, a smile like never before formed on her face.

The following day, every slave was called to stand in front of King Fritz, his eyes looking at each of his slaves with contempt, they were shaking in fear, knowing someone had done something, and now all of them would get punished for something someone else did, some were even crying but not begging for mercy... yet.

"Last night, someone let the pigs for tonight's feast free; tell me which one of you did this; if you don't, I will take one eye of each one of you. A slave doesn't need two eyes," the king spoke, his booming voice immediately registered by everyone, especially the slaves. They immediately started shaking in fear, some slaves looking at the others as if trying to see who was responsible. Soon two slaves set their eyes on Ymir, who, unlike the rest, wasn't showing much fear.

Hearing his words, two slaves stood up, their eyes blank of emotions like that of a corpse, before pointing their fingers at Ymir, who until now had shown no sign of fear or nervousness; feeling their glares, the girl started shaking, her eyes looking down at her feet, scared.

More slaves stood up, pointing their fingers at the girl, thirteen fingers pointing towards Ymir. The girl felt her heart beating in her throat. Seeing who was the one responsible, the king ordered Ymir to stand up and walk toward him.

As soon as Ymir was five feet away from the king, a soldier grabbed her arms from behind, holding her, Ymir tried to do anything to run away, but she was not stronger. She couldn't run anywhere.

"One eye for nine pigs," the king ordered, soon followed by the girl's screams.

But that wasn't the end; soon after, the King ordered her slave to run away into the woods; Ymir reluctantly obeyed before running away; as soon as she disappeared amongst the trees, several knights with horses started riding toward her while shooting arrows where they thought she should be, to them was only sport.

Ymir ran through the forest, her bare feet aching like never before, soon bleeding from all the sharp rocks she steeped on; suddenly, she fell to her knees, her skin bleeding from the small stones that pierced her skin around her shin and knee. She felt as if her shoulder was on fire; her arm instinctively touched where it was burning, soon touching something sticking out of her shoulder; an arrow had pierced her shoulder; despite the pain, Ymir stood up again, herself not knowing why she kept running, tears flowing freely from her left eye.

Soon she found a tree much larger than the others, with a big opening at the bottom; knowing this could be a safe place to hide, Ymir walked inside, pitch-black inside, not seeing anything in front of her; Before stumbling and falling for what felt like forever, she didn't even felt her body slamming against the surface of the water, slowly sinking below, Ymir felt herself cold but no longer feeling pain, not breathing, she knew this was her end.

Suddenly from the corner of her eyes, she saw what looked like a bug approaching her from behind with interest; a second passed.

Nothing

Two seconds

Nothing

Three seconds

Nothing

Nine seconds

Ymir suddenly felt a sharp pain on her spine before it disappeared as quickly as it appeared, everything went white, the next thing she knew, she was higher than she had ever been before, the trees were suddenly tiny, everything was below her feet, every animal was smaller than her now, everything was looking up at her now instead of down on her.

That day, Ymir became the very first Titan. Soon to be known as Ymir, The Founder.

The knights chasing her died when she transformed, and the tree fell, except for two soldiers who were a bit away from the others, frozen due to the shock of seeing a monster like her before being trampled by her.

But instead of seeking freedom, Ymir returned back to her king; everyone quickly noticed the changes around her body; every scar and even her missing eye was healed. The skin of her body looks clean; she no longer feels pain, no longer covered in dirt.

Knowing what an opportunity he had in front of him, The King quickly removed the title of 'Slave' from her and even freed slaves that were quick to blame her for the missing pigs, but Ymir wanted to release them.

Not even a month later, Ymir and her king's army went to war with their biggest rivals, the Marley Tribe.

The army of Marley Tribe was stronger and had more soldiers; their weapons were better, swords, spears, shields, everything was better.

When they reached the battlefield, they saw the monster of Eldians, who quickly killed every soldier in her way, some tried to kill her, but their weapons hardly even scratched her skin, let alone pierced it. Due to her Titan powers, she easily defeated every army sent against her; the soldiers froze from the very image of her Titan.

Soon the rumors spread far and wide, the rumors of a monster—a monster sent by the devil himself.

Because of her achievements in Eldian's wars, King rewarded her by marrying Ymir.

Ymir soon had three daughters, Maria, Rose, and Sina. Despite being daughters of Ymir, they showed no Titan powers, but Ymir could tell something there was hidden.

Fighting more and more wars, Ymir was soon known as a goddess amongst the Eldians, even making statues in her Honor. The one which people of Eldia prayed to, many kneeled to her feet the moment they saw her, bathed in glory and the blessing of the gods.

And a Devil to everyone else, someone that needed to die, but it was well known that Ymir could heal herself from everything, at least that's what it was known; every scratch and even bleeding and stabbing would quickly heal as if it was never there, something that her daughters were shown to have as well.

Because of that, Ymir knew there was a way to unleash their powers, but despite many tries, nothing happened at first, until her nieces and nephews were born.

At age 63, Ymir used a power, a power she had never used before. No one knew what happened or what she did, but a day after using that power, Ymir suddenly fell sick; on her dying bed, she separated her powers to nine Titans amongst her nine nephews and nieces, that was soon known as the big nine families.

The Titans were soon given names based on their abilities, The Founding Titan, War-Hammer Titan, The Colossal Titan, The Armor Titan, The Beast Titan, The Cart Titan, The Jaw Titan, The Female Titan, and The Attack Titan.

No one knew except Ymir and her daughters about the secret ability of The Attack Titan, something Ymir swore them never to reveal to anyone; the ability was something that even Ymir knew was dangerous if it fell into the wrong hands. She would keep it secret until she knew that day would come.

After Ymir's death, everyone who inherited their titans died within 13 years. That Curse was soon known as The Curse of Ymir.

But throughout the years of wars and conquest of Eldia, several people were known as the Blessed Eldians since, despite inheriting their Titan power, they weren't affected by the curse of Ymir. Dying at old age, Not only that, but these people were stronger than the others; their Titans were always stronger, it didn't matter which one they held, their Titans were always stronger, faster, bigger, and more durable.

One Blessed Eldia, who held the Colossal Titan, was a hundred meters tall instead of the usual 60-70 meters.

The Jaw Titan, used by a Blessed Eldian, stood over twelve meters tall, and his jaw and teeth were made out of diamonds with sharp edges.

Every century there would be three people that weren't affected by the curse, always three people each century.

No one knew what caused it, they were many times when they tried to understand the reason why, but no one knew, and it was completely random, not something that happened to a specific Titan; it could happen to all nine Titans at random.

Before dying, Ymir Fritz made a vow, something that was kept secret amongst her daughters but was never revealed to anyone else, soon being forgotten with time.

After years of war and bloodshed, Eldian fell when the 145th King, Karl Fritz, planned the downfall of his own people and empire. The nine families started fighting each other for the power of the Titans.

A war soon ensued, The Eldian Empire fell, and Marley took over everything. Karl Fritz runs away to a nearby island with many of his subjects but still leaves behind thousands of Eldians, losing Seven of The Nine Titan powers. The Attack Titan was killed during the war and was never found again.

Karl Fritz soon, with the power of The Founding Titan, turned millions of his subjects into Colossal Titans, creating three big walls and leaving a Warning to the outside world to leave them alone or the millions of Colossal Titans would trample every piece of land outside of Paradis Island, and making his own people forget about the outside world making everyone believe that the rest of Humanity was devoured by Titans.

The Blessed Eldians never occurred again after the fall of the Eldian Empire, a century passed, and every Titan Shifter died thirteen years after inheriting their Titan abilities.

The curse of Ymir caused whoever was a Titan Shifter that during their thirteen years since gaining their power, they would age very fast; within eleven months of their thirteen-year, they would age as if decades had passed. Not only that, but if a Titan shifter used their Titan during their Last Year, it would be very costly, resulting in sickness and even earlier death.

Marley treated every Eldian they had like less than human; at a young age, they were taught they needed to pay for what their ancestors did and that the Eldians on the Island were devils. Every man, woman, and child who was suspected or even said something pro-Eldian in public would be sent to Paradis Island. Hell, all it took was one Marley to simply point the finger at an Eldian for them to be sent to Paradis.

During the first fifty years after the fall of the Eldian Empire, Marley kidnapped over a hundred children from age one to five, sending them to Paradis Island to see how the serum reacted to them, resulting in small titans that could not even walk, let alone be a danger to anyone in the island.

Marley made sure to spread the propaganda that Paradis was filled with devils that deserved nothing but death. Some knew that wasn't true or that it was all propaganda, but the majority of Eldians believed the lies.

Marley tried to understand why they never had any Blessed Eldian, but soon they decided to drop it since they had enough Eldians to sacrifice to the Curse of Ymir or simply turn them to mindless Titans to be dropped to the enemy territory and hoping for the best. Soon Marley was the one controlling the biggest power in the world due to the power of the Titans, but their biggest asset soon became their biggest weakness.

Grisha Yeager

He had been sure that he would be eaten by a Pure Titan that was a former friend, and worst of all, he would die by the same bastard that killed his sister.

As the bastard tried to push him down, he didn't even have time to process as the other officer pushed him down, Grisha gasped at seeing what the Marley officer did, but looking down, he saw the man lose all color on his face, in front of him standing the same titan he had tried to sent Grisha too.

Screaming in fear, he immediately tried to run away, but he didn't even get to take a single step before the titan grabbed him tightly, the force alone breaking his bones, but he ignored all that as he saw the giant teeth coming towards him.

"No NONO, PLEASE," He begged as he tried to push his giant face away with his arms, but the titan simply bit a small part of his face; he was still alive as he felt all the pain, his face skin hanging out, his bones visible, and his head bleeding, his blood covering his mouth as he kept screaming in pain.

"NONONO PLEASE NOOO-" He went silent as the giant teeth bit down half his body, snapping his spine in half, killing him.

During all this, Grisha kept his eyes closed; he wanted to see him suffer, but in the end, he closed his eyes, not being able to handle it; the screams alone were terrifying, making every part of his body shudder, the thought of that kind of fate alone made his heart sink to the deepest of voids.

"Who are you?" Grisha asked, turning to the man who saved him; the man threw the hat away before glancing down at him.

"I'm the Owl, and my name is Eren Kruger."

After introducing himself, Eren quickly killed every Marley soldier left before sinking the ship they arrived with.

Eren told Grisha that he needed to reach the walls and find the Founding Titan; the Eldian needed a new King to save them from Marley and the rest of the world.

"How can I do all that? I can't," Grisha spoke with a tired voice; his son had betrayed him and Dina, oooh Dina, I failed you, I failed you too, Zeke, he thought, feeling his eyes welling with tears; he had been a horrible father. If only he had been there for his son, to spend more time with him, how much he wanted to apologize, to make up for everything he did, but it was too late, Grisha knew he would most likely never see his son ever again, he would never be able to apologize.

That's all Grisha wanted right now, to hold his son and apologize for everything he did. Falling to his knees, Grisha felt a hand on his left shoulder.

"Stand Up. Remember what they did to your sister; you need to keep going. You have to keep moving forward." Eren spoke to his left; Grisha barely reacted before he felt a hand on his right shoulder.

"You will meet Zeke again if you do it," a voice spoke in the wind; quickly turning to his right, Grisha saw nothing but the sea; no one was there. His mind soon proceeded what the voice said, Will, I truly be able to see Zeke again?

Turning to Eren, Grisha soon stood up, turning to the officer. "I will give you The Attack Titan, with his secret ability, you will be able to find it; for the sake of Armin, Mikasa, and the rest of Eldians, you should prevail," The Owl said; Grisha raised an eyebrow with confusion written all over his face.

"Who are Armin and Mikasa?"

"Who knows, I don't know whose memories are these!" Eren simply said with a shrug as the sun was behind him, shining on both of them, making their shadow cover a big amount of land behind them.

"You can see the future. Is that the ability you were talking about? Is that the secret ability of The Attack Titan?" Grisha asked with astonishment.

"No, I can only see small glimpses, but the secret ability of this titan is a different one. The Attack Titan has a special ability that was lost with time; no one before had ever used it, but I believe in him."

Grisha didn't know who he was talking about; Eren was talking as if he was talking to someone else; his eyes weren't focused on him, but instead to his right, but Grisha couldn't see anyone else.

Turning to look at him again, Grisha coughed, gaining his attention. "What is this ability?"

Eren looked at him with uncertainty, not knowing if Grisha needed to know about that; several seconds passed in silence as if to wait for something; Grisha saw Eren again, looking not at him before his eyes found Grisha again.

"Ymir The Founder kept that ability hidden from everyone except her daughters. The ability to-" Grisha's eyes widened at what he heard from Eren, sweat rolling down his face. He didn't ask any questions, and he didn't need to.

"If Marley were to know about this, they would have absolute control of the whole world and knowing how they treat people that aren't Marleyans." Eren finished with a shudder of his body; he pulled a little box from his coat, giving it to Grisha.

Grisha glanced at the officer before turning his eyes to the little box in his hands; opening it, he saw a syringe filled with blood and spinal fluid.

"Why there's blood in the syringe?"

"The blood is a secret, but the spinal fluid, I took it from the many syringes that Marley has with Spinal fluid. With time you will understand it, as did I," Eren stated with a weak smile, jumping down in the sand. The pure Titans had left long ago; the area was clear. The only thing left was the corpse of the Marley, who the titan ate.

"Do it now, Grisha, soon you will know the truth," Eren said firmly; Grisha grabbed the syringe; he looked back at the man who saved his life, respect in his eyes.

"Thank you for giving me a second chance," Grisha shouted respectfully before injecting the syringe into his arm, quickly jumping down; suddenly, a flash of yellow lightning came where he was.

Eren simply stood; he didn't try to run away; Grisha's pure titan form was soon revealed, standing 17 meters tall, with long dark hair, but unlike the other pure titans who usually had big grins, Grisha's face was sad. There were three red lines below his eyes that reached his jawline, the same line a Titan Shifter had when they came out of their titan.

Eren smiled; it worked, he thought with a smile as Grisha grabbed him with his big hand; Eren simply closed his eyes. He didn't scream; he didn't beg for mercy as the jaw of the Titan closed on his spine.

After The Fall of Shinganshina

"Wall Maria has fallen; everyone will be devoured!"

"Wall Rose will fall next; run for your lives!"

As they rushed north, the people yelled. Despite the fact that the titans were nowhere near the town, the mere image of lumbering giants coming towards their families drove practically everyone mad, driving them to seek the safety of Wall Sina.

Keith Shadis couldn't avoid being swept away by the large group of people. He'd given up his position as Scout Commander, and now he was nothing more than a bystander. Nothing out of the ordinary. It's never been, and it'll never be.

"Keith!" He was jolted out of his funk by a voice from behind him. His boots dug into the earth, and his body became an immovable obstacle for the residents around him to avoid rather than wash down the stream with the others. Dr. Grisha Jaeger, an old friend, was approaching him as he turned around.

"Please, Keith!" Once the two had finally joined each other in company, the guy appealed. "Please help me find my wife and son".

Keith answered slowly, as if in astonishment, "They'd be at the shelters." Keith moved quickly when Grisha pushed him to steer the path.

As they ran into the shelters, the only source of light they had were the torches. For both of them, everything seemed to be a fog, and time seemed to be immaterial.

Shadis' footsteps awoke several of the sleeping refugees, who watched him with alarm as he gazed at each individual he passed. He departed and shut the door behind him when no one recognized him. Then he halted as he saw Grisha standing outside a shelter, holding an unconscious Eren.

Where is Carla...? He thought.

Grisha crouched down and placed Eren on the ground, his arm supporting the boy's head.

"Wake up, Eren." He softly cooed and gently shook his kid till he received a reaction. Eren groaned, his voice harsh. His eyelids twitch when the faint light of the flames shines through. His father's face was the first he saw.

"Dad...?" He gave a shaky greeting. The horror came back to him, and he began to shake, tears welling up in his eyes. "Mother, she—". Eren closed his eyes and cuddled up against Grisha's cloak, resting on it. He bawled, "A rock wrecked our house...A titan... I couldn't do anything, I gave it my all!" Eren sobbed on his chest.

Grisha was cradling his shivering kid, without a tear streaming down his cheek. To the untrained eye, the guy seemed to be unaffected by anything that had occurred. Keith, on the other hand, knew him better. He was in excruciating pain on the inside, but he refused to let it consume him. It was one of the numerous characteristics that distinguished the guy, something he could never achieve.

"Eren, come with me," Grisha eventually said. He gave the command while holding his son's hand and assisting him in getting up. "We're going to get revenge for your mother." As he led them toward the forest.

"What?! Grisha? Where are you going, exactly?" Keith yelled their names.

"The forest. Keith, please don't follow." Grisha responded quietly once again.

"You want to take revenge for what happened to Carla? But why are you dragging your child into this nightmare, how do you know he's special like you? What makes you think he's not a bystander like me??"

Grisha spoke nothing but turned his head, his glare almost making him shiver in fear. But Shadis quickly noticed that Grisha's eyes weren't looking at him; he was looking at something else.

"This boy is different from you; he is my son that I love more than anything. Stay Out of This," Grisha said with a tone that promised pain to whoever dared to disobey him. Shadis felt a shiver down his spine.

Grisha saw the other figure disappear; the moment he saw him disappear, he knew it was the moment to change everything.

That was the last thing Grisha said to him before the two disappeared into the trees.

As he led them away, Eren looked up at his father, eyes still running like facets. He led them deep into the forest before letting go of Eren's hand and pulling something out of his pocket. When he turned to face his son, his eyes were shiny with tears.

Grisha remembered what the future showed him; it was a dark future that would result in the downfall of all Eldians and the rest of the world; Grisha knew he needed to do something to change that future, anything. This World was A Cruel World.

Looking down on his son, Grisha knew what he needed to do; he knew it would hurt; Eren had already lost his mother, Carla, I'm sorry.

But Grisha knew his son still had Armin and Mikasa, especially Mikasa; he didn't need to be a genius to know the girl saw Eren as more than simply an adopted brother. The way how she tried to protect him was admirable, the way her face would blush the moment Eren would play or do anything fun with her.

He will be in good hands, and if everything goes as I planned, No, it Will Go; there's Just No Other Choice, he thought.

"My son, sit with me. I need to tell you something," Grisha said warmly and with a hint of sadness.

Removing his coat, he spread it in the grass before gesturing for Eren to sit there; the kid sat down, still looking at his father's eyes; despite trying, Grisha couldn't stop the tears. His Carla was gone, but he knew soon he would reunite with her.

The screams were still fresh on his mind, his hands crushing the children; how could he ever forgive himself for that, but Grisha believed in the future; Kruger had shown him that future; he needed to believe the man who gave him a second chance in life.

Grisha knew Eren would have a hard life full of challenges and sadness, but he truly believed there was beauty in this cruel world.

"My son, I need to tell you something; what I will tell you is something you can never tell anyone unless you trust the person with your life until the time is right. Promise me, Eren," Grisha said with clear desperation in his voice; Eren had never seen his father like that but quickly nodded his head.

"I promise you, Father," Eren promised with a tone that showed that he truly meant it.

Grisha felt somehow relieved before kissing his son's forehead, taking a deep breath to calm himself. Opening his eyes, he opens his mouth to speak...

"A long time ago, there was a girl named Ymir, she was known as Ymir The Founder, she was the very first Titan-" Grisha went on and explained everything that he knew about the history of Eldians, only leaving out the part about the Curse of Ymir, he explained how the 145th King hated the amount of bloodshed his own people had caused, before planning the downfall of his own empire. He explained how Marley treated the Eldians across the sea," Grisha stopped talking, letting the information sink in; Eren's eyes were wide open, but he didn't ask anything for now; he wanted his father to end his explanation first.

After several seconds of complete silence, Grisha started explaining what the king did, creating the walls and making everyone on the island forget about the Outside World.

"The Owl, that's what he called himself; he gave me a second chance at life. When I entered the walls, it didn't take long, and I met your mother," Grisha said with a smile; Eren, for the first time since the fall of Shiganshina, smiled back.

"I remember when you were born, it was one of the happiest moments of my life," Grisha said, hugging his son, allowing himself a tiny bit of happiness, despite knowing that he didn't deserve it.

Eren hugged his father back before pulling away; his father's face changed to a sad one again.

Eren wanted to ask so many questions; he wanted to ask how why Marley would attack them? How the world out there was? Many questions? He didn't even know what he wanted to ask first.

"Eren, I know I'm putting a lot of responsibility on your shoulders, but my time is running out," Grisha spoke grimly; Eren's smile fell as soon as he heard his father's word.

"Whatttt??" Eren tried to speak, his voice hoarse.

Running his hand through his hair, "Listen, Eren, I don't have time to explain everything, but" Grisha grabbed something from his coat, revealing several pages written from top to bottom and also a small box; inside were four syringes filled completely with what Eren thought was blood.

Grisha put the coat away from them before turning back to his son with a syringe in his hand.

Kneeling in front of his son, Eren couldn't help but feel something was wrong. The feeling of dread spread through his whole body.

"Why don't you have time to expla-" Eren's question was interrupted as his father started coughing loudly, so much that he fell on the grass.

"Father, Father" Eren shouted, worried, trying to look at his father's face, only to see his eyes had almost turned red now, his mouth bleeding, and so was his nose, his face pale like snow.

His father's condition made Eren freeze in horror, but he quickly pulled himself together, knowing he needed to help him.

"Father, we need to get you to a doctor, Right Now," Eren shouted, grabbing his shoulder, trying to get him to stand up, using his own body to help him, but Grisha shook his head; there was nothing he could do, no one could do anything. Grisha always hoped that he would be a blessed Eldian, to save his son from the cruelty of this world, but it seemed fate had again laughed in his face.

My son will be one, he thought before using all the strength he had left to grab his son's arm.

"Listen, Eren. I'm sick, my time is running out, and after the last usage, I'm already a foot deep in the grave. This is not something that can be cured; I did everything I could with the time I had left. But you can, my son, unlike me, I know you will succeed in building a home for all Eldians." Grisha spoke with a sad smile, blood leaking from his mouth into his chin before dripping to the ground.

Eren wanted to tell him that he could be saved, that it wasn't too late to save his life. "No, I won't, Los-"

"Read my letters after you wake up; they will explain what I didn't have time to," Grisha pleaded as he prepared to inject the serum into Eren's hand.

Eren tried to push it away, "No, father, what are you doing?" He cried; Grisha used the last bit of his strength as he plunged it into his arm.

"If you want to save Mikasa, Armin, and everyone else... You must learn to control this ability!"

Grisha Yeager could only cry as he injected his son with the serum. He knew what he was forcing upon his son, a life full of pain and suffering. The difficulties and trials his son would be forced to go through in order to prevail would undoubtedly scar the boy, but this was his only option. This was the only way!

His tears only increased as Eren screamed in pain; Grisha snapped his eyes close and turned his head away as he pushed more of the Titan blood into Eren's bloodstream. 'Carla, Mikasa, forgive me... Eren, I'm sorry I had to do this to you, but this is the only way for us to survive!'

Pulling the needle out of Eren's arm, he could only watch as a sudden flash of light enveloped his son. When the light receded, all that was left was a monster, a titan. A deep sigh was released from Grisha's lips as if he was truly relieved of some great task. Eren, or the pure titan he had now become, snatched Grisha up within its tight grasp. Grisha felt his body weakening under the immense pressure of his son's titan grip.

"Carla, Dina, I'm sorry I couldn't save you. Zeke, my son, I love you, and I'm sorry for everything I did to you. Eren, I hope you live a long and happy life."

The man looked upon his son turned titan as acceptance coloured his eyes. He was ready as he continued to look into the eyes of the titan that would consume him. 'My work is complete; at long last, I can rest.' Even before the thought was complete, the seven-meter titan had closed its jaws around Grisha's frail body and snapped it in half.

The seven-meter titan that Eren had become consumed his father, unknowingly setting the man's plans into effect. The titan collapsed to the ground as Eren emerged from the steaming titan corpse. However, that wasn't the worst the boy would have to endure by the time the night was over.

Eren looked at his hands, tears streaming down his face; what was left of his father's corpse was right beside him, his glasses on the ground; Eren picked them up before letting out a cry of despair.

"FATHERRR"

The following chapter will have Eren's reaction to the Truth. Why did Grisha inject Eren with Titan blood mixed with spinal fluid? Why are there three other Syringes?