Requested by Legendarygoji

Transformers vs Attack on Titan, Alien Robot vs Ancient Monster, Autobot vs Titan, Hero vs Destroyer,  when two giant leaders with opposing values of war meets in battle, they will keep moving forward until oneshall fall

<Cue: Invader Theme>

Toomi: Optimus Prime, the leader of the Autobots,

Megumi: And Eren Jeager, the Titan Shifter of the Survey Corp,

Toomi: When in the face of war, some will do whatever it takes to fight for the survival of their own kind,

Megumi: And these two can transform as well! She's Sachi, Toomi and I'm Megumi.

Sachi: And it's our job to analyse their weapons, armor and skills to find out who would win a Death Battle

Optimus Prime rolls out in What if Battles

<Cue: You've Got The Touch by Stan Bush>

Toomi: Millions of years ago, on a distant planet called Cybertron, a great unrest grew between two factions of robotic beings, the Decepticons and the Autobots. With little warning, they found themselves entangled in civil war.

Megumi: And leading the Autobots is the fearless and strong leader Optimus Prime where with his leadership, the Autobots wage their battle to destroy, the evil forces of the Decepticons.

Sachi: But he wasn't always Optimus Prime. In fact he used to be an ordinary robot by the name Orion Pax until Megatron gunned him down.

Megumi: What Megatron didn't know was that this seeming random encounter would end up reshaping the universe.

Toomi: With the help of Alpha Trion, Orion Pax was rebuilt into something bigger, stronger, and way more recognizable. And this was where Optimus Prime is born.

Optimus: Freedom is the right of all sentient beings

Toomi: Being a Cybertronian or most commonly referred to as a Transformer, Optimus Prime well transforms. He can scan nearby objects and morph his body to resemble one, becoming a robot in disguise.

Megumi: His favorite is a classic 1979 Kenworth K-100 tractor, an oldie but a goodie which sports 500 horsepower and can book it over 80 miles per hour. He even gets a trailer, which, when he doesn't need it, mysteriously disappears into thin air. No, really. Where the hell does that thing go? I need to know.

Sachi: More importantly, the lifeforce of every Transformer resides in their spark, sort of like a soul, and Optimus is no different, except that his spark gives him a few unique abilities.

Toomi: It gives him increased strength, speed, and durability. He can shoot laser beams from his hands, fly with either a jetpack or his feet boosters, and move his limbs around while their detached

Megumi: Optimus Prime is also equipped with some sick weaponary, those include a standard ion blaster, a blaster with impressive fire power to destroy any Decepticon, an axe which he can use to cut up Decepticons and even swords and axes made of Energon to do pretty much the same thing, slicing.

Optimus Prime

Master Combatant

Master Swordsman

Expert Marksman

Master Tactician

Expert Leader

Ion Blaster

Fusion Axe

Energon Swords

Jetpack

Command Deck module

Trailer unfolds to reveal weaponry

Roller module

Small drone kept inside the trailer

Matrix of Leadership

Toomi: Even then, many of Optimus' abilities are further enhanced thanks to his possession of one of the most powerful artifacts in Cybertron's history: the Matrix of Leadership. Now, the matrix is a conduit for the power of Primus, the creator of the Transformer race. With this, Optimus can heal some of his most grievous wounds and even damage Unicron.

Megumi: Geez, not surprising considering the Matrix of Leadership is literally part of a Robot God.

Toomi: It wasn't long before Cybertron's war eventually made it to Earth but with an Autobot like Optimus here, humans have no need to worry. Especially when Optimus has tanked blasts that would tear other bots apart. Like when this mega-refinery exploded, it could be seen from outer space! He's punched the ground so hard the trees around him exploded.

Megumi: He's thrown a satellite into orbit, and punched hard enough to crack Sixshot's chest plate.

Sachi: Who boasted that his armor was drawn from the compacted subatomic matter from a collapsed star. Just to let you know, such a star would have a density of over 300 billion tons per cubic inch. While great density does not necessarily beget great toughness, this still means that Sixshot's armor was 500 billion times more dense than osmium, the most dense natural material on Earth.

Feats

Lifted the 81,000 ton Washington Monument

Shot a ship in space from ground level

Dodged shots from the Fusion Cannon

Survived an exploding mega-refinery

Moved a 724,000 ton oil tanker

Withstood a wormhole collapsing on him

Commanded 1,000 battle via the Omniglobe

He, along with Megatron, saved the universe from and were forced to (supposedly) kill and put an end to Shockwave

Defeated the Stunticon combiner Menasor single-handedly

Officially annexed Earth into the Council of Worlds

Commanded 1000 battles on multiple fronts via the Omniglobe.

Cracked Sixshot's Ununtrium armour, which is composed of materials drawn from the core of collapsed stars.

Punched through Monstructor's chest with his bare hands.

Survived getting stepped on directly by Trypticon and lived.

Survived a mega-refinery explosion that was big enough to see from outer space with seemingly no injuries.

Defeated Megatron while fatally wounded

Brought back as a zombie by the Quintessons, only to break their control and give up his second chance at life to go in a suicide run in a shuttle to destroy their fleet, and his body was still intact after the resulting explosion

Cured the Hate Plague across the universe via the Matrix of Leadership

Managed to beat Megatron, who survived an explosion powerful enough to push Cybertron out of Earth's orbit, to near-death with nothing but his bare hands.

Outraced a tidal wave while riding on a surfboard.

Survived a fall from orbit with minor damage.

Separated Devastator into the individual Constructicons with a single shot of his Ion Blaster.

Ion Blaster can reach targets in orbit from ground level in just a few seconds.

Defeated and incapacitated Bruticus with Starscream and Megatron's help.

Helped created the Aerialbots.

Can easily tear apart fighter jets with his bare hands.

Gave his life to stop the Swarm, filling it with Primus' vision of the Transformers via the Creation Matrix, thus changing its mentality to beings of creation and restored Prime to make amends

Defeated Megatron, Menasor, Monstructor, Sixshot, Swindle, Soundwave, and Nova Prime.

Defeated his universe's Unicron, by showing its still living creator compassion, allowing him to rest in peace as Unicron's body collapsed into a black hole as a result, killing all three in the process.

Toomi: Optimus has even taken down many powerful villains, having broken free from the Quintessons, bested Megatron who once tanked an explosion big enough to knock Cybertron out of orbit and with the Matrix of Leadership, he defeated Unicron.

Megumi: Who you can imagine to be basically the Transformers equivalent of Marvel's Galactuc.

Toomi: Optimus is certainly powerful, but after all is said and done, he has one major weakness...

Optimus: Perhaps you can condone widespread human casualties Agent Fowler, I however...cannot.

Toomi: Too nice.

Sachi: Yeah, he's kinda all about the whole 'honor' and 'fair fighting' thing, which kinda screwed him over more than once, and even gotten him killed!

Megumi: Not once. Not twice. Multiple times. In fact never mind G1, whether it be Animated, Prime, or even the Bayverse, Optimus has died at least once in every remake of Transformers history.

Weakness

Versions of him across the Transformers multiverse have, at some point, died at least once

His compassion for all forms of life can be used against him

Tends to back his full strength as he is afraid to harm those around him or even the planet he's on

Toomi: But as most Cybertronians are, Optimus requires Energon for energy for if he were to run out, Optimus Prime can go offline.

Sachi: And his reluctance to harm humans, even if they want to do harm to him has ends up becoming a massive downfall to Optimus.

Megumi:  But when his back is to the wall and all hell's breaking loose, he'll fight to the end, riding the eye of the storm.

Optimus Prime: One shall stand and one shall fall

Eren Yeager Titan-shifts into What if Battles

<Cue: Monster by Kanye West feat Jay Z, Rick Ross, Nicki Minaj and Bon Iver>

Toomi: Eren was born in the Shiganshina District of the outer Wall Maria to Karla Yeager and Grisha Yeager,  where the last traces of humanity took refuge in after the rise of the giant man-eating monsters called Titans.

Megumi: So when Reiner as the Armored Titan and Bertholt as the Colossal Titan bursts in, sending Titans into the District where Eren watches his mother get eaten by a Smiling Titan who turns out to be Grisha's first wife, it messed him up pretty quickly.

Sachi: So with his best friend Armin and his adoptive sister Mikasa, Eren enlisted in the military's 104th Trainee Squad five years later alongside Mikasa and Armin, Eren eventually places fifth overall in his graduating class.

Toomi: But it was there where Eren gotten eaten.

<Shows footages of Eren getting eaten by a Titan.>

Megumi: Welp, that's the end of the series. Roll the credits! Heh. Just kidding.

Toomi: Although things may look like it's all over for him, Eren however began doing the unexpected, transforming into a Titan and he began attacking every Titan around.

Megumi: So Attack on Titan. Heh.

Sachi: So how did Eren become this Titan you may ask? Well as it turns out, Grisha also forcefully injects a serum in Eren's body that transforms him into a normal 6-7 meter Titan that devoured Grisha before reverting back to human form

Toomi: Before Eren, Grisha turns out to be a Titan shifter himself, he is the Attack Titan, one of the Nine Titans besides Armored, Female, Colossal, Beast, Jaw, Cart and Founding Titan. The Attack Titan is described to be a Titan that fights for the freedom of Eldia no matter the day and age. While all of the Nine Titans could receive memories of past inheritors, the Attack Titan could also receive memories of inheritors yet to come. These memories led those with the Attack Titan to move forward, fighting for freedom

Megumi: And thanks to Miliatry training and lessons taught by Reiner and Annie who turned out to be his future enemies, Eren possesses incredible strength and fighting techniques, capable of decapitating Titans of equal size or shattering the jaws of even the Armored Titan with one punch.

Sachi: As it turns out the Attack Titan isn't the only Titan Eren has acquired. During the battle at the Marley district, Eren killed the Warhammer Titan by consuming Lara Tybur, thus gaining the Warhammer's ability to create spikes made out of the same hardening material.

<Shows footages of Eren creating spikes out of the Warhammer Titan's ability to attack both Reiner and Porco.>

Eren Yeager

3D Maneuver Gear

Expert Martial Artist

Great Swordsmanship

Coordinate power

Titan Shifting

Super Strength

Peak Level Endurance

Healing Factor

Regeneration

Memory Reading

Hardening Ability

Memory Manipulation

Warhammer Titan crystal construct

Weapon Construct

Toomi: But the Warhammer Titan is not the only Titan Eren has. As it turns out, eating his own father also gave Eren the power of the Founding Titan, which gives him the ability to control all Titans and manipulate the memories of most people once belonged to the Reiss family, whose ancestor could have ended the Titans' attack on humanity but deemed them a necessary evil to ensure peace and instead created the walls while altering the memories of those who now live within his city save the nobles, the dwindling Asian populace, and the Ackerman family

Sachi: However, by the time Eren frees Ymir Fritz in the Paths, Eren instantly is granted full possession of the Founding Titan, building himself a gigantic titan body that towers over the walls several times over and is able to undo all forms of titan hardening around the world in an instant

Megumi: And he can even create hollows of former dead Titan shifters like Bertholt's Colossal Titan and Porco's Jaw Titan to protect and fight for him.

Toomi: Having the strongest Titan on his side means that out of everyone in the Survey Corps, Eren holds the highest Titan kills amongst all characters, even being deemed the strongest normal cadet below Mikasa who is an Ackerman and Reiner, Bertholt and Annie who had training prior to joining the corps.

Sachi: He has even held his own against several Titans in battle, even being ganged up by the combined might of the Armored, Jaw and Cart Titan, even weakened Eren has caused grevious injuries to them.

Megumi: And after the Marley declared war on him, Eren basically brought the war to them, being solely responsible for the mass casualties in the state, even killing Wylbur and Lara Tybur in the process.

Feats

Eren has the highest Titan kill record by far of all the former graduates of the 104th Trainee Squad, though it mostly in Titan form as he only killed one as a human with the 3DM gear.

Ranked 5th among the 104th Cadets, under the three Marley Warriors and Mikasa Ackerman, the former of which trained extensively prior to their arrival and Mikasa possessing near-superhuman qualities.

Took two human lives at age nine, justifying his actions as killing "animals".

Killed over 20 Titans during the Battle of Trost in Titan form.

Eaten alive by a Titan and survived

Endured severe bleeding injuries and being IMPALED through rage alone

Defeated the Female Titan

Broke the Armored Titan's skin.

Helped kill Rod Reiss's titan, which stood 120m tall

While fending off the Jaw Titan at the same time, defeated Ms. Tybur in Marley and inherited possession of the War Hammer Titan by consuming her remains.

Defeated the Colossal Titan with Armin's help

Has the power to control Titans (but can only do so in contact with Titans of royal blood)

Infiltrated Marley's capital and killed their heads of office with his Titan form

Regenerated from decapitation by an anti-titan rifle

Influenced the events that led to the acquisition of his Titan powers through his father's memories

Convinced Ymir Fritz to awaken the Wall Titans and grant him full control of the Founding Titan

Wiped out a large majority of humanity with The Rumbling

Most recent titan form capable of matching Armin's Colossal Titan

Toomi: But the most horrifying thing is that spoiler alert for those who never read the manga is that with the power of the Founding Titan, Eren lead an army of Titans across the globe where they plowed through the combined Military efforts of the global alliance and wiped out pretty much 80 percent of the world population.

Megumi: Damn. And to think that Eren was only a young kid when he had his first human kill, it's shocking how many he has wiped out.

Toomi: However, Eren isn't without his flaws, despite his strength, some of the Titans has beaten him before with the Female Titan besting him in their first battle and the Colossal Titan even sending him flying with a single kick.

Sachi: Not to mention aside from the enhanced abilities Eren's Attack Titan achieved throughout the years, the Attack Titan has no unique abilities of it's own, having no armor, no powerful jaw, no crystal constructs or even a Beast like appearance.

Megumi: And Eren has only two Titan kills as a human, killing one with his blades and killing the Colossal Titan with Armin's help.

<Showing footages of Eren killing one Titan with his blades>

Megumi: Ha! Imagine going through all that trouble just to learn how to use the ODM gear, even almost failing the enlistment just to use it only once.

Weakness

Survivor's Guilt, feels undeserving of his power

He can be blinded by his own anger, but overcomes this as the series progresses

Once lost both arms and a leg (both in just a few minutes)

The colossal titan once gave him a kick that sent him flying against one of the walls.

Defeated by Female Titan twice (once in her titan form)

Punched across a forest by the Armored Titan

Titan shifting requires his mind to focus on a single objective or goal, then the titan body decays once its purpose is fulfilled. If his mind is reluctant, he cannot transform.

The Attack Titan on its own does not seem to possess any notable or unique abilities like the rest of the Nine Titans

In his Titan form, his rage can be uncontrollable and prompts him to sometimes attack allies or go a tad overkill

INCREDIBLY reckless. Has earned the nickname 'Suicidal Bastard' as a result.

Regrowing limbs as a human is possible, but is a time-consuming process and disables him from turning into a Titan until he is fully healed.

Using his hardening ability places additional strain on his body

Overusing the War Hammer's power will drain him of stamina

Eventually becomes capable of transforming several times in succession, but this has limits.

Has killed only ONE TITAN with his blades

Was completely unfamiliar with his Coordinate abilities early on

Because he is not descended from Eldian royal blood, he cannot use the Coordinate unless he makes contact with titans of said bloodline.

Due to a curse that came with his titan powers, Eren has 13 years to live following the possession of his power, and thus 4 years left to live as of now.

The Founding Titan's influence has no effect on people without Eldian blood or the Ackerman clan.

Toomi: But the biggest weakness of any Titan shifters is that after acquiring a Titan, they can only live for 13 years before he dies, which means at where he is currently at in the anime, he has 4 years left to live.

Sachi: And he is incredibly reckless. Gaining the nickname "Suicidal Bastard" because of it.

Megumi: But one thing is for certain that Eren has taught all of us, peace can never achieved until every human is dead.

Eren: I just keep moving forward...until my enemies are destroyed.

Toomi: Alright, the combatants are set, let's end this debate once and for all.

Sachi: Don't forget to vote, comment what you think of the fight.

Megumi: Yeah, but right now, it's time for a Death Battle!

Fight

Paradis Island

In the outskirts of the wall of Wall Maria, Titans surrounds the district, preparing to attack any humans that moves.

Up on the top of the wall, a tall man with a hair tied in a bun faces the Titans only to notice something moving from the distance.

VROOOM!!!

Driving out of the forest is a shiny red and blue firetruck, driving towards the rows of Titans.

The Titans notices the truck and they began approaching the vehicle.

But what happens next is a shocker.

<Cue: Transformers G1 intro>

The truck began morphing, transforming from a truck into a giant robot.

TSCHE!!! TSCHE!!! TSCHE!!!

Eren widens his eyes with intrigue as the robot dashes towards the Titans, fearlessly declaring out.

<Cue: Transformers EVO by JAM Project>

Optimus: My name is Optimus Prime, Leader of the Autobots and you shall not harm the humans of this planet!

As the Titans closes in onto the Autobot, Optimus Prime throws one powerful punch, instantly snapping one of the Titan's neck with a single blow.

POW!!!

The Titan is sent flying, knocking down several other Titans as Optimus draws out his Ion blaster, opening fire at the recovering Titans.

PIU!!! PIU!!! PIU!!!

Eren Yeager scoffs and he curses.

Eren: Tch. Such nuisance

Eren then zips out with his ODM gear, using the Titans as his vantage point as he draws out his blades, closing in onto Optimus Prime just as the Autobot caught his gaze.

Announcer: Fight!

Eren swings his blades down onto Optimus, only for the blades to shatter upon contact with his plating.

Optimus swing his hand out, sending Eren flying with a strike.

WHAM!!!

As Eren is sent flying, he looks down lifting up his hand as he took a bite down onto it, causing lightning to crackle as he began transforming as well.

THOOM!!!

Optimus looks up from his Titan kill, noticing something happening to Eren as he mutters out in shock.

Optimus: By the Matrix.

Eren's titan's eyes glows as he rears up his head, letting out a loud roar.

Eren: RROOOOOARRRR!!!

Eren has transformed into the Attack Titan!

Eren lands feet first across Optimus, staring at him as Optimus spoke out.

Optimus: By the Allspark, I shall defeat you!

Eren: GROOWWWLLLL!!!

Both Optimus and Eren sprints towards each other, raising up their fists as they each throw a punch.

BAM!!!

The hardening material on Eren's fists began cracking Optimus' face plate while at the same time, the metallic plating of Optimus' fist shattered Eren's jaw.

Despite his injuries however, Eren raises up his other arm, grabbing onto Optimus before attempting to hold the Autobot leader in a lock.

However, Optimus easily lifts Eren up before slamming him hard onto the ground.

THOOM!!!

Optimus brandishes his axe as he raises it up, preparing to finish Eren off when...

SHING!!!

Utilizing the power of the Warhammer Titan, Eren summoned several spikes made out of hardening material, one of them piercing Optimus through the chest in the process.

Bleeding energon and stuck, Optimus spoke out in surprise.

Optimus: This is something I did not expect.

Eren began scaling up the spikes, heading straight towards the now pinned Autobot but Optimus is still anywhere but out of the fight.

Using his axe, Optimus shattered the spike before transforming back into his truck mode.

TSCHE!!! TSCHE!!! TSCHE!!!

The truck nose dives right towards Eren, slamming right down onto him.

WHAM!!!

Eren: RAAHHHHH!!!

Eren roars out in agony as he falls back first, crashing onto the ground as Optimus drives onto the rocky road before reconverting back into his robot mode.

TSCHE!!! TSCHE!!! TSCHE!!!

Eren pushes himself up as Optimus commands.

Optimus: Stand down.

Eren however, grabs Optimus by the leg before giving it a tug, tripping Optimus down as Eren began kicking him repeatly in the face.

THOOM!!! THOOM!!! THOOM!!!

Optimus however, brandishes his axe and he gives it one hard swing.

SLASH!!!

Eren: RAAARRRRHHHHHH!!!

Eren lets out one loud roar as blood spills from the wound where his leg once was.

Optimus tosses the leg aside before he pins Eren down, punching him three times in the face.

BAM!!! BAM!!! BAM!!!

Optimus: Stand down.

Optimus repeats.

Eren instantly summons more spikes with the Warhammer Titan's ability, piercing Optimus through his body once against.

SHING!!!

SHOK!!!

Eren: RARRGHHHHH!!!

Eren lets out a loud roar as he pushes himself up, throwing a combination of punches across Optimus.

WHAM!!! BAM!!! POW!!!

Optimus recovers from the blows and just as Eren lunges forward, the Autobot leader swings his axe upwards, slicing Eren through the neck.

SLASH!!!

Eren felt his head fly off his body, with the Autobot having decapitated him.

As Eren's head continues falling, Optimus stood gravely over him and he says.

Optimus: It's over.

The fight however, is still far from over.

<Cue: Kissin U' by Miranda Cosgrove>

BZZZTTTT!!!

Electricty sparkles around Eren's body as a large skeletal like aspandage resembling a spine erects from the Titan's socket, plunging into Eren's head as the Titan Shifter undergoes another transformation.

Optimus watches, dumbfounded by the process as he mutters.

Optimus: By the Matrix...

Optimus shifts his head up, watching as Eren began growing larger and larger until he stood towering over the Autobot.

Eren has transformed into the Founding Titan!

Eren then lets out a loud roar.

Eren: ROOOOOOAAAARRRRR!!!

The loud ear splitting roar travels across the district, causing the walls to crumble.

RUMBLE!!!

But what happens next shocks Optimus Prime.

Stumbling out of the wall are a large number of giant humanoids resembling a skinless human, marching through the crumbled heaps of debris as they follow under Eren.

Bringing in the Wall Titans, Eren began sending a telepathic message towards the Titans, ordering them to attack Optimus.

Optimus widens his eyes.

Optimus: No...

Almost immediately, the army of Colossal Titans began marching through the town, crushing through wall and buildings as Optimus prepares to take them on.

The army of Titans closes in as Optimus Prime activates his Energon Axe, slashing at the Wall Titans as the energy from the blade began cutting through them.

SLASH!!! SLASH!!! SLASH!!!

Now towering over Optimus Prime, Eren began slowly moving towards the Autobot, the Founding Titan summoning the Female, Armor, Beast, Jaw, Cart, Attack, Warhammer and another Colossal Titan to attack.

Optimus Prime lunges forward, grabbing the Female Titan before slamming her down into a building.

CRASH!!!

He then throws a left hook upwards, shattering an Armor Titan's jaw.

CRACK!!!

As a Jaw Titan jumped onto Optimus, the Prime grabbed the Titan before swinging it out, using it's body to strike into a Beast Titan.

WHAM!!!

Optimus tosses the Jaw Titan aside before grabbing a Cart Titan, decapitating it with his Energon Axe.

SLASH!!!

As a Warhammer Titan swings it's mallet at him, Optimus grabs onto it before giving the weapon a hard tug, pulling the Warhammer Titan towards him

He then grabs the Warhammer Titan, keeping it in a neck lock.

He takes the mallet and hurls it at an approaching Attack Titan before snapping the Warhammer's neck, shattering it in the process.

Optimus then flies up as he throws one powerful punch, creating a massive explosion upon hitting a Colossal Titan's head.

BOOM!!!

As the Colossal Titan collapses onto the floor, Optimus lands feet first onto the ground as he looks up.

Despite defeating the eight previous versions of the Nine Titans, Optimus still finds himself surrounded by the army of Titans.

However, despite the odds, Optimus faces the Titans fearlessly, declaring out.

Optimus: As long as power flows through any of my circuits, I will not surrender. I'll take you ALL on!

The Wall Titans began closing in onto Optimus, attempting to grab onto him.

Optimus points his ion blaster, shooting one of them in the head before swinging his Energon Axe across the leg of another, killing two of them only for the third Colossal Titan to grab onto him.

Optimus: ARGHHH!!!

As the Colossal Titan lifts Optimus up, the Autobot leader quickly converts back into his Truck mode, squeezing himself free from the Titan's grasp.

TSSCH!!! TSSSCH!!! TSSSCHE!!!

Optimus drove along the arm of the Colossal Titan before leaping up, transforming back into his robot mode.

TSSCH!!! TSSSCH!!! TSSSCHE!!!

Optimus then throws one powerful punch, sending the Colossal Titan tumbling down into another, causing them to fall.

Activating his jet boosters, Optimus flies through the army of Colossal Titans, narrowingly dodging every swing as he fires his Ion blasters at them.

THOOM!!! THOOM!!! THOOM!!!

Activating his Energon axe, Optimus slices through the neck of a Colossal Titan before flying up towards Eren, declaring out.

Optimus: You have no soul!

Inside the Founding Titan, Eren shouts back.

Eren: That is why I have no fear!

The Founding Titan then summons a Jaw Titan to leap onto Optimus, causing the Autobot to slice it through with his Energon Axe.

SLASH!!!

Eren then swings his hand out, sending it slamming right into Optimus.

WHAM!!!

Optimus: ARGHHHHH!!!

His jet boosters damaged, Optimus finds himself plunging downwards before crashing into the ground below.

CRASH!!!

Thinking he had won, Eren then mutters to his Titans.

Eren: Finish him

The Colossal Titans began surrounding Optimus Prime, preparing to finish off the Autobot leader.

However, Optimus still has one more ace up his sleeves.

SHING!!!

Optimus body began glowing brightly as he unleashes a powerful aura, setting off the surrounding Titans in a massive explosion.

KABOOM!!!

Eren looks down, noticing that Optimus now engulfed completely in an overwhelming aura.

Opening his chest piece, Optimus aims the Matrix of Leadership at the Founding Titan as he declares out.

Optimus: With the power of the Matrix, one shall stand and one shall fall!

THOOM!!!

The powerful blast strikes Eren right in the head, causing it to go off in a massive explosion.

KABOOM!!!

As Eren's head falls off the Founding Titan's body, just as it was about to hit the floor, right at that moment, someone caught his head.

Holding Eren's decapitated head is Mikasa, who stood there, solemnly pulling Eren's head close as she silently give him a goodbye kiss.

While Mikasa quietly mourns Eren's death, Optimus stood over the collapsed and inactive Titans around him

He then throws his axe down onto one of the Wall Titan's head, standing up tall as he stood victorious from his long battle against the Titans.

In this battle, he has conquered the giants and saved humanity from extinction.

<Cue: Compound I Love You by Jincheng Zhang>

Megumi: My God, if only Attack on Titan would have ended like this. Who knew all it took to end the Rumbling is a firetruck voiced by Peter Cullen himself.

Toomi: You said it. Anyway, with both their experience in combat and warfare, Optimus and Eren has many ways to counter each other, even almost kill each other in combat.

Sachi: Like Eren's Hardening to match Optimus' metal plating, Warhammer Titan's hammer and spikes to counter his weapons along with Optimus ion blaster to counter Eren's healing factor along with Optimus' having longer experience in the battlefield to counter Eren's relentlessness.

Toomi: However, while Eren defeating the likes of Reiner, Annie, Porco and Lara is impressive, that is nothing compared to Optimus defeating Megatron, a gladiator who fought his way out of the Deception pits which is better than young teenagers who has lack of experience in a battlefield.

Megumi: But when Eren turns into the Founding Titan, he gained both the number and size advantage over Optimus so now you might think that alone should be enough to kill Optimus right?

Sachi: Except Optimus has defeated an enemy way larger than the Founding Titan. You guys know who that is?

Toomi and Megumi: Unicron.

Sachi: While Eren's Founding Titan form may be larger than some skyscrapers even in today's standards, Optimus fought and defeated Unicron, a Transformer larger than a planet itself.

Toomi: Especially even if Optimus cannot kill something as the Founding Titan with his weapons alone, his Matrix of Leadership being the part of Primus that created Cybertron would provide more than enough firepower to take down the Founding Titan.

Megumi: And since Optimus has fought armies of Decepticons, monsters and defeated the likes of Devastor, I wouldn't worry too much about how he would fare against the Rumbling.

Sachi: Too bad there isn't any Linkin Park music to play after this.

Toomi: Holding the upper hand in strength, power, strategy, skills and experience, we can conclude that Optimus holds the keys he needed to bring the Attack on Titan.

Megumi: Looks like Optimus still Got the Touch while Eren didn't have his head in the game.

Sachi: The winner is Optimus Prime

Optimus: At the heart of every legend, there is truth: a few brave souls unite to save the world. We can be heroes in our own lives, every one of us, if we only have the courage to try. Our fates were always intertwined, but now our worlds are joined as one. We need to repair our planets, work together, if we wish to survive. A dangerous secret is buried deep inside the Earth. There is more to this planet than meets the eye. I am Optimus Prime, calling all Autobots: It is time to come home.

Toomi: Hey guys, thank you so much for checking out our battle in What if Battles 2.

Sachi: If you want more content like this, don't forget to add this in your library and comment if you have any idea for a fight.

Megumi: Until then, next time on What if Battles...

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VS

Merlin

Tatsumaki vs Merlin

Trivia

* The connections between Optimus Prime and Eren Yeager is that both combatants were warriors who started off as normal before becoming a hero or threat to their friends and enemies, the two having a high kill count as they fought against the evil forces of tyranny and dictatorship, the Marleyans for Eren Yeager and the Decepticons for Optimus Prime

* The two possesses transformations with Eren being able to turn into the Attack Titan, Warhammer Titan and Founding Titan while Optimus can alternate between his truck and robot mode

* Both are also an arch nemesis to a strong brawler, Megatron for Optimus Prime and Reiner Braun for Eren Yeager

* However, both combatants can be seen as polar opposites as Optimus Prime is a hero who has lead his allies with compassion and leadership, even sparing his enemies whilst Eren Yeager hurts his friends, killed innocent people and became the world's biggest threat along with them having contrasting ideologies with Optimus fighting to restore freedom while Eren fights to wipe out his enemies

* Another contrast between their characters is that while Optimus Prime does not condone human casualties and would do whatever he can to protect them, Eren not only killed humans as a kid but is even responsible for wiping out 80% of the entire human population

* This is the first time a Transformers character fights an Attack on Titan character

* This is the first time a Transformers character wins a What if Battle

* This is the first time an Attack on Titan character loses a What if Battle

* This fight is most likely created to commemorate the release of Attack on Titan Season 4 part 2 and the upcoming Transformers Rise of the Beasts

* The part where Optimus Prime transforms in the start of the battle is based off the final battle scene in the G1 Transformers movie

* During the fight, Eren uses the Warhammer Titan ability to create spikes to stab Optimus is based off his fight against Reiner and Porco where he utilized the ability to stab both the Armored and Jaw Titan

* Optimus Prime taking on the Wall Titans during the Rumbling is a homage to Hanji Zoe's death as they fought and killed three Colossal Titans to help buy the Survey Corps time to escape except unlike Hanji, Optimus killed a large majority of Titans without dying, even coming off victorious in the fight

* Optimus Prime shouting "I'll take you ALL on" is based off his quote from the movie Transformers Revenge of the Fallen

* The part where Optimus says to Eren that he has no soul and Eren retorting that this is why he has no fear is a reference to Optimus' fight with Galvatron in the movie Age of Extinction

* The ending of the fight featured Mikasa from the previous Attack on Titan battle, Mikasa Ackerman vs Blake Belladonna where she mourns Eren's death which is a reference to the ending of the Attack on Titan manga

* Optimus' victory line is based off his last line in the movie Transformers The Last Knight