AN: The premise of this story will follow three changes in the storyline. The first what if Eren wasn't there to save Mikasa in time and she was killed on accident by one of the kidnappers by struggling against them? The second what if Hannes was killed by the same titan that killed Eren's mother and Eren was able to get his ODM gear off of him and went on a rampage since he wasn't forced to leave that area by Hannes? The third what if Eren's memories weren't as affected as his father thought they would be from the injections?

AN: As you can see shit's going down for Eren in this. He is my favorite character in Attack on Titan and I wanted to a write a story where he's a complete bad-ass due to those three changes.

Disclaimer: I do not own Attack on Titan

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Year 843, Wall Maria, Zhiganshina District

A young boy around eleven years of age was currently running deep into the nighttime woods in search of a cabin holding four people in it. The scene he had witnessed earlier having deeply ingrained him to the reality of his world. That it was kill or be killed, no matter if it was the Titans that plagued their world or the humans fighting and killing each other.

The boy had short brown hair and jade green eyes. He was dressed in a cloth white shirt with a brown long sleeved jacket over it. He had a red scarf wrapped around his neck and dark brown pants on his legs and brown shoes. His name was Eren Yeager.

The scene he had witnessed earlier was horrifying but also led to a small hope. Two members of the Ackerman family, a long time client of his dad's who was a doctor, had been slaughtered in their own home and their daughter missing most likely kidnapped by slave traders.

Eren just stood there looking at the scene with wide eyes while his dad shouted at him to snap out of it. Before he knew it he was running through the woods looking for the girl and her kidnappers knowing they couldn't have gotten far due to the blood being fresh on the bodies.

A few minutes later he found a cabin with the lights out. Gritting his teeth he grabbed the hunting knife in his pocket he used to cut down firewood with and charged inside. Not even taking in the scene before him he stabbed the first guy he ran into in the stomach and savagely ripped the blade out sideways splashing blood everywhere. Spinning around when he heard movement he slashed the blade straight out in front of him and luckily hit the guy behind him in the throat as the guys knife that had lunged at him only scored a mark across his cheek.

Once that guy dropped to the ground holding his throat to futilely preserve his life Eren's adrenaline had run out and he had a chance to take in the scene in front of him. It caused to him to drop his knife and take a shaky breath.

There on the ground were two bodies. One was another man with his chest having a broom handle impaled in it and the other was a little girl Eren's age with a her throat slashed. They were both dead.

He dropped to his knees and looked at the little girl. He hadn't been in time to save her. Just then his dad came rushing in.

"EREN!" Dr. Yeager yelled as he walked in and seen the bloodstained room and his sons blood covered form.

Eren turned his dead eyes over to his dad and shook his head slowly as he pointed at the girl. Tears were beginning to come out of his eyes as his dad hugged him.

"Why are humans doing this to each other? Titans are the enemies not each other." He said as he cried into his dad.

"Sometime humans can be worse Eren. Greed and Lust are just two of the sins that turn humanity on each other." Dr. Yeager said holding his sons head to himself.

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Year 845, Wall Maria, Zhiganshina District

A now thirteen year old Eren was laying down in a field of flowers sleeping. He still wore the same clothes just bigger to fit him better. He also still kept his scarf around his neck.

Just then he awoke with a gasp after having a nightmare about the scourge outside of the walls coming in and massacring everything. He looked around and rubbed his eyes before getting up and grabbing the pack he had that carried the firewood he gathered. Putting it on he ventured into town to head home.

Once he was halfway home he heard the bells above the wall begin going off. He looked up with a smile and ran towards the gate knowing what that meant.

A few minutes later he was fighting his way through the crowd to get a view of his heroes. He stood up on a crate and finally was able to see them riding in on their horses. He looked at them with an excited smile. They were all dressed in the military outfits with their signature green cloaks wrapped around them with the wings of freedom emblazoned proudly across their backs.

He caught a tall blonds man eye as they walked but when he turned his head away in shame from Eren's eyes he suddenly noticed the mood, and as if his vision shifted he all of a sudden could see the various many injuries sported by the Survey Corps. How they all walked with an aura of gloom. He could see carriages made for carrying body's filled almost to the brim.

Just then an elder lady walked up to two of the soldiers asking about her son. One of the soldiers the commander by the looks of it handed her a wrapped bundle which seemed to startle the woman. She unwrapped it before gasping as it contained the arm of someone, her son most likely, before she dropped to her knees and began sobbing hysterically.

She stayed like that for a few moments before saying something that surprised the commander. "Did he help? Even if it was something useless by distracting them did he help us advance humanity's territory!" She yelled desperate for an answer.

"Y-Yes, I mean no, I-I mean we never learn! All of this is my fault, my inexperience led to all of these deaths!" The commander yelled falling to his knees.

A few moments later the corps carried on mood even more soured.

"Tch, looks like all of our taxes are going to waste fattening up the titans." One of the civilians next to Eren said to another villager who nodded along with him.

Gritting his teeth Eren punched the man in the face knocking him down. "Don't you dare say that about them! Their the reason humanity will one day be able to go beyond the walls again and claim back our world!" Eren yelled at him before he ran off before the angry man could get up and get back at him.

He however didn't notice the blonde corps member watching him the whole time though.

A little while later he was at home depositing the firewood he gathered in the crate they held it in while his mom was preparing dinner and his dad sat at the table drinking coffee going over his notes.

"Wow Eren you gathered a lot today." His mom said smiling at him as she set the table.

"Yea I guess." He said with a sigh as he sat down next to his dad.

"Something wrong dear?" His mom asked as she set some food on his plate along with his dad's and hers.

"The Survey Corps returned today." He mumbled getting his dad's attention along with his moms. "However it was another failed venture, and to make it worse no one appreciated what they do for us! That's why when I turn fifteen I am enlisting and am going to join the Survey Corps." He said getting more passionate.

"What!" His mother gasped. "Eren do you know how many people die on those trips!" His mother yelled at him. "Dear talk some sense in your son." She said pleading with her husband.

"Eren why do you want to join the Survey Corps?" His dad asked him in a calm tone.

"Because if someone doesn't continue their work then all of their sacrifices will have been in vain!" Eren answered him heatedly.

"I see." His dad said nodding as he stood up. "I need to be going I have to get some ingredients. I will be back in two to three days." He said as he walked out of the house.

"Dear wait you and Eren need to have a long talk on why he shouldn't!" His wife said following him out along with Eren.

"Honey, Eren needs to make his own choices and it seems he is set on this. Nothing we say is going to change his mind." He said before waving them goodbye as he left.

Once he was gone Eren's mom turned to him. "I won't let you go and sacrifice your life like that." She said to him.

"I am not going to be content to be cattle for the titans!" Eren yelled at her before he ran off.

"Eren!" She yelled at him before frowning sadly.

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A few minutes later across the town

"Take that you heretic!" A kid said punching a blonde kid into the wall.

"Why don't you fight back huh?" He asked him as his two friends beside him laughed.

"Because that would put me on the same level as you! You fighting means you know I am right and don't want to answer!" He said shouting back at him.

The kid widened his eyes before gritting his teeth raising his fist to hit the blonde kid again when a shout stopped him.

"Hey cut it out!" Eren shouted as he was running down the street. The three kids looked over and paled.

"Oh crap it's Eren! Run!" They shouted before running away.

Once Eren caught up the three were already gone. "Tch, cowards." He muttered looking at them run before looking at the blonde kid.

"Hey Armin are you alright?" He asked him as he put a hand out for him to take.

"I can stand for myself." Armin muttered getting up.

"Well alright." Eren said with a raised eyebrow seeing Armin stand up.

A few minutes later the two were sitting on a river bank throwing rocks into the river.

"So what happened?" Eren asked.

"I said that one day humanity will need to leave the walls to explore the world and see it for ourselves, but they called me a heretic." He explained.

Eren narrowed his eyes and nodded. "I see. I don't know why people are so content to spend their whole lives in these walls, living like cattle." Eren stated throwing a rock harder than normal.

"That's why I am going to join the survey corps and see the world with my own eyes." He continued.

Armin was just looking down. "Yeah just because the walls haven't been breached in a hundred years doesn't it won't happen….like today." He said with a dark look.

All of a sudden they heard a huge explosion and looked off into the distance towards the wall to see smoke rising.

"What was that!?" Armin yelled.

"I don't know let's go check it out!" Eren said back before the two ran to where a crowd was gathering.

When they reached the crowd they looked up to where everyone was looking and widened their eyes. A massive hand was gripping the top of the wall. Then a huge shadow fell upon them as a colossal head revealed itself.

"B-But that wall is 50 meters high!" Armin yelled in shock.

Then the titan raised it's leg and kicked it right into the gate blasting it open sending out a huge shockwave along with giant pieces of debris. Eren and Armin had to close their eyes to block them from the wind and when it died down they opened to see Titans coming in through the hole. Everyone who had been watching in shock began running away in terror in the direction of wall Maria's gate.

Eren stood rooted to his spot however as he realized one thing. "My house is in that direction." He whispered. He then took off running towards his home.

"EREN!" Armin yelled seeing Eren run towards the titans. He himself was too scared to even move. He did get his feet going however and ran back towards his home to get his grandfather.

With Eren he was running as fast as he could towards his home. "When I go around this turn my home will be there and it will be fine." He told himself but when he rounded the corner, and widened his eyes in fear, he started running harder.

His house was smashed by a boulder.

Getting closer he found his mom on the ground covered in pieces of the house. "Mom!" He yelled seeing her.

Carla blearily opened her eyes and looked up to see Eren trying to lift a huge support beam off the bottom half of her legs. "Eren! Run away and escape!" She yelled at him.

Just then they heard and felt loud footsteps. Eren looked up to see a huge titan coming in their direction. He widened his eyes and kept trying to pry the beam off his mom.

"Their here aren't they? Eren leave me and run, my legs were smashed in the collapse I can't move!" She shouted at him.

"What are you talking about I am going to free you and were running away together!" He shouted.

"Why don't you ever listen to me! At least listen to me this once!" She yelled hysterically crying.

Just then Hannes a close family friend landed next to them using his gear.

"Hannes take Eren and run!" Carla yelled at him.

"Don't worry I am going to defeat that titan and save the both of you." He said smiling as he began running in the titans direction.

"No you can't!" Carla yelled at him.

A few seconds later Hannes body came flying back and hit Eren sending them both flying back.

Blinking his eyes in pain Eren groaned as he looked up to see Hannes dead glassy eyes looking down at him as blood ran down his face. Eren widened his eyes and rolled Hannes off of him and looked over in the direction of his house.

He looked just in time to see the titan bend down and brush away the debris and lift his screaming and struggling mom in the air.

"N-No." He whispered. The titan grabbed his moms head and snapped it backwards before lifting her towards it's mouth and snapping it's mouth down biting her body in half.

Eren watched this all with wide eyes. Then something within him snapped. Gritting his teeth he grabbed Hannes body and dragged it into the house they were next to. He titled his head out the window and noticed the titan hadn't seen him yet and was just standing there at his house with it's creepy grin.

He looked down at Hannes's body for a few seconds before getting to work. He removed all of his ODM gear before equipping it onto himself. He had to readjust the belt for his small size. He had watched Hannes and his squad train countless times and knew how to use the gear. Once it was all adjusted he walked back out of the house.

It was just in time to see the titan devour the lower half of his mom's body. Narrowing his eyes in rage he roared as he attached two blades to the handles and shot the cables into a building behind the titan and then flew threw the air.

"AHHHHHHH!" He yelled as he spun threw the air before smashing the blades right into the titans nape where he heard Hannes tell him was the weak spot on a titan. Once he reached the other end he sheared his blades out as the titan fell to the ground dead. He landed on a building and watched the titans steaming body fall to the ground decomposing.

"I'll kill them all!" He growled out. "I'll wipe out every titan there is!" He yelled as he looked at all the titans looming around the town. Pulling the trigger on the ODM he launched himself into the air.

[Play Attack on Titan OST]

"Hah!" Eren yelled as he sliced through his third titan riding it's body to the ground. For some reason he could feel something pulsing deep within himself as he fought, radiating electricity through his every nerve. It was making him go faster and striking stronger.

He was flying through the city striking the napes of every titan he came across, even saving some civilians in the process yelling at them to get running to wall Maria.

Striking down another titan somewhere around his ninth he broke the last of the blades he got off of Hannes's body. He was also running low on gas.

Eren landed on the ground near another dead soldier with his equipment still intact. Repeating the process he did with Hannes he took off his empty canister and switched it out with the soldiers as well as taking his blades.

He used the gear and leaped onto another roof. More and more titans were still spilling in and he could see people still evacuating in the distance at wall Maria. Knowing what he had to do he started flying towards the wall.

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With the Garrison forces helping evacuate

One soldier was looking out over the city through a telescope to get the range of how many titans were still coming. Spotting something approaching them however caused him to widen his eyes.

"Captain you have to see this!" He yelled over to his captain who was still assisting civilians.

"What is it Cadet?" His captain asked as he walked over to him. Wordlessly the cadet passed the telescope over to him. The Captain looked through it in the direction the cadet was pointing for a few seconds and widened his eyes.

"What is he doing?" He whispered to himself before he seen the kid they were watching turn around and slice the nape of a titan killing it and then station himself on a roof a few yards in front of them watching the road killing any titan that came near him.

"He's defending the gate!" The captain realized with shock.

"Cadet send reinforcements and help that kid! He's risking his life to insure we all get out safely and I will not be the one let him die in doing so!" The captain ordered.

"Sir!" The cadet said saluting before he ran off and gathered a few troops before they used their gear and leaped in the kid's direction.

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Back with Eren

Eren roared as he killed his twentieth titan, breaking his last set of blades again. He fell on top of another roof out of breath and sat there for a second to catch it. All of a sudden a shadow loomed over him and he looked up to see a titan grinning as it reached out to him.

Gritting his teeth he brought the broken blade up ready to shear it's fingers off before all of a sudden a soldier came flying in striking the titan in the nape killing it. He then seen four other soldiers land on the rooftop next to him.

"Hey kid you alright?" The one in the lead asked him as he helped him up.

"Yeah but I broke my last set of blades again." Eren said raising up the broken blades.

"That's what your worried about?" The soldier asked shocked before he put his hand on his face and laughed. "Kid your amazing! Putting ODM gear on yourself and killing titans to aid in the evacuation." The soldier said before he removed a set of blades from his sheaths and handed them to Eren. The other three soldiers doing the same refilling Eren's blades once again.

Eren looked up at them in confusion.

"You'll need them more than us kid. As it painful as it is to admit your killing more of these things than we are and can probably keep doing so. We've been sent here to help you defend the wall until the evacuation is finished." The soldier informed him.

Eren nodded before he turned to look at the titans that filled the city as he detached the broken blades and attached new ones.

All of a sudden they felt and heard heavy footsteps near them. As one they turned in the direction it was coming from only to see an abnormal titan rounding a corner. It was armored in bone plating. The titan lined itself up with the gate of Maria and lowered itself into a runners stance.

Eren widened his eyes upon seeing this.

"It's going to charge the gate and smash it! We need to stop it!" Eren yelled as the titan took off in a charge.

He shot his ODM gear in it's direction and went flying along with the other soldiers.

Eren was the first to reach the armored titan, he shot his cables in a wall adjacent to it and flew through the air towards it's nape.

"Hahhhh!" Eren yelled as he spun through the air his blades made contact with the titan but they broke instantly on the armor. Eren widened his eyes seeing this as he landed on the roof he attached his cables to.

"It's nape is armored! Aim for it's joints on the legs! Slow it down so it can't ram the wall!" Eren yelled out to the other soldiers.

"Okay!" They all yelled.

The first soldier to reach it's joints missed but the second managed to score a strike on it's ankle, but it seemed the bulky titan ignored them and kept charging.

"Were not going to make it in time! Beat it to the wall and kill any titans that come through so everyone can have time evacuate!" Eren yelled changing his plans in the middle of the battle seeing that it wasn't going to work.

The soldiers nodded and sped through the air along with Eren bypassing the titan that was ignoring them.

They made it through the gap in the closing gate just in time as the titan smashed into it coming to a sliding stop on the other side.

The civilians seeing this began to panic and started running screaming in fear.

"Continue with the plan! Give them time to escape!" Eren yelled out to all the soldiers present as he killed the first titan to emerge on the other side.

"Yes sir!" The squad that was with him from the beginning yelled involuntarily saluting as they followed his lead. This caused the other soldiers there to follow them in either killing titans or assisting civilians to escape.

The armored titan meanwhile released a huge cloud of steam and disappeared just as suddenly as he appeared just like the colossal titan.

Meanwhile on the boat Armin and the others who knew Eren had wide eyes as they watched him valiantly fight to protect them from the titans.

"How are you always so strong Eren?" Armin whispered to himself watching Eren fighting and killing titans keeping them away from the civilians.

A few hours later the soldiers and Eren were sitting on the rooftops away from the titans, tired and out of breath.

"Sir the evacuation is complete, all of the living civilians have been taken away by the boats." One of the soldiers said saluting to Eren.

Eren looked at him confused. "Huh why are you saluting to me and not reporting to your captain there." Eren said pointing to the captain who stood beside his soldier saluting Eren as well.

"I mean I'm just a kid." Eren continued in a confused manner.

"Just calling you a kid is an insult to your skills. You took command over all of the squads here and expertly lead them to battle saving countless lives. If you weren't here, I fear the results of today would have been ten times more grave." The captain explained to him.

"I know you haven't heard yet but their calling you the Hero of Zhiganshina." He further explained to a shocked Eren.

"I see. Well since everyone's evacuated you guys can have your gear back. I'm going to see if I can find my dad, he left on a trip to wall Rose this morning." Eren said as he began undoing the straps on his equipment before he could however the Captain put his hand on Eren's stopping him.

"Keep it. You have more than earned that gear, should we meet again I will gladly follow you into battle once more. It was an honor to serve under your command Eren Yeager!" The captain said as he proudly saluted followed by every other soldier there.

Eren lowered his head at that. "Thank you." He whispered before he launched his ODM gear and began heading towards Trost the closest district to find his dad and Armin.

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That day from humanity's darkest hour, a legend emerged. Reports from hundreds of survivors and soldiers detailing the accounts of the Hero of Zhiganshina gave humanity hope that they could one day claim lands beyond the walls from the titan menace.

The year after that was a hard one for Eren. He had found his dad but something was different about him. He was crying and acting strange. He had injected Eren with some kind of serum and said it would be a power he could use to retake wall Maria.

The serum had knocked him unconscious barely hearing what his dad said after that.

"Eren never let go of this key, and every time you see it remember you need to make to the basement of our home. In it is all the answers to everything. This serum may affect your memories so just remember to look at that key everyday. I know you will make me and your mom proud. Also don't fixate on just killing the titans, learn to live your life maybe find a girl and make each other happy." Dr. Yeager said to his barely conscious son.

He looked up and sighed as he heard the transformation begin. "I have to go now my son, we will not see each other again. Her memories will teach you how to use this power, so remember retake wall Maria and make it to the basement!" Were the Doctor's last words as he was devoured.

A few moments later Eren awoke to find his fathers remains and cried out in horror before passing out in exhaustion.

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When Eren came to he found himself in a warm bed. He could clearly remember what happened despite his fathers claims that his memories would be affected. He cried to himself for hours upon realizing what his father did to him and what this meant. After a few hours of just laying there he felt his resolve harden and he got up and went outside.

After that those two years of waiting to enlist flew by for Eren as he went through his daily motions. Their was a bad food shortage due to the massive influx of refugees from wall Maria, and to solve it the government sent thousands out beyond wall Rose to scavenge for food. It was nothing but a scheduled massacre, due to the governments inability to deal with the situation.

Armin even lost his grandfather in that event, which is what pushed him to want to enlist with Eren in the army. Food was never to hard to come by for Eren due to his status and the respect that came with it made the soldiers give him food first.

Eren felt bad that he was being prioritized instead of the more hungry but he knew he needed to survive so that he could battle titans.

Then finally in the year 847 he and Armin had enlisted and they were lined up with the other cadets for their fist day of the training that would last the next three years.

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Boom first chapter is done! Please leave a like and a favorite and let me know what you think in a review!