Requested by Flamewarrior11 and humatrix-X-24

When two teens who can transform into aliens gets into a fight, only one can be the victor

Athius

Martial Arts Skils

Expert Marksmanship

Rage Mode

Gear

VB-10X Rifle

Stun and kill function

Omnitrix

Has all of Ben's original aliens inside

Has the Ultimate and Fusion function

Feats

Beaten Vilgax and Albedo

Defeated Ma Vreedle by hitting her with a blast from Atomix at point blank range

In Rage Mode, he cannot be stopped

Weakness

Goes into rage mode if others mocks him about his parents abadoning him

After using his Ultimate and Fusion forms, his Omnitrix must recharge for 20 minutes

Karen

Martial Arts Skills

DNA mimicking

Power Absorption

Able to turn herself and her limbs into her version of Ben's original aliens

Feats

Spent her early days as an Esper in Academy City

Becamed a skilled street fighter

Able to take on the powers or skills of anyone she comes across

Able to implement her alien forms and implement her powers into her own fighting style

Beaten many of Ben's enemies

Manages to copy the skills and abilities of a thousand Espers

Able to handle all of Ben's powers

Reached the power to go Ultimate

Learned how to use her different powers and combine them, making her very versatile

Weakness

Rash

Cocky

While her Defenses are superior, her offensive attacks are weaker in comparison

Extremely competitive

Tends to resort to cheap shots and even flashing her chest in order to get things her way

Does not kill despite her competitiveness

Fight

Mount Rushmore, outside the Rustbucket

It was a nice Sunday afternoon, birds were chirping as the sun blazes across the sky.

On the peak of the mountain, Ben lay down lazily on a beach chair, shifting himself into a comfortable position whilst holding onto a Mr. Smoothie cup.

Ben: Aahhhhh!!!!

As Ben lay down, relaxing on his beach chair, Kevin steps outside of the Rustbucket and he greets his friend.

Kevin: Hey Tennyson.

Ben turns back and he returns Kevin his greeting.

Ben: Oh hey Kevin.

Kevin approaches Ben, lowers himself onto a rock before sitting himself down onto the surface area of the rock.

Kevin turns his head towards Ben and he questions him.

Kevin: So, watcha doin' Tennyson?

Ben: Oh nothing, just sitting back and watching my proteges spar.

Ben and Kevin turns and the two watches as a boy and a girl faces each other.

Athius, a tall teenage boy cladded in a green jacket and armed with an Omnitrix, smirks and he said to his opponent.

Athius: I'm definitely going to win this Karen.

Karen, a young teenage girl with blue hair, green shirt and jeans, slowly morphs her arms into an emerald green crystal spike and she said.

Karen: Nuh uh. I'm gonna beat you down Athius!

Athius places his hand on his Omnitrix and he began turning it, switching through his mass collection of aliens

As Athius stops at a Diamond type sentient, he moves up his hand and he scoffs.

Athius: We'll see.

BAM!!!

Athius's skin began shifting, his flesh crystalizing into a spiked,  armoured creature.

As Athius transforms, his eyes glows yellow before he clenches his diamond fists.

Athius has transformed into DiamondHead!

Athius morphs his arms into a crystal blade and he points it at Karen.

From afar, Ben looks up from his beverage and he calls out to the two.

Ben: Remember you two! Give it everything you got!

Athius and Karen narrows their eyes and the two acknowledged in unison.

Athius and Karen: With pleasure.

Both Karen and Athius sprints towards each other and they swung their Diamond blades, clashing against each other.

CLANG!!!! CLANG!!!! CLANG!!!!

Athius grunts as he throws a punch.

However, Karen quickly forms a shield with her diamonds and she shielded herself from the attack.

CLANG!!!!

Karen morphs arms into two huge overly muscular scaly arms, resembling that of Humongosaur.

Karen raises up her fist and she throws a punch.

BAM!!!

Athius: ARGH!!!!

Athius screams out as he was sent flying backwards from the attack.

Karen morphs her entire body into that of Wildmutt and she launches herself towards Athius.

Karen: GROAR!!! RRR RR!!!

However, just before she could pounce on top of him, Athius taps the Omnitrix symbol on his chest.

BOOM!!!! SHHT!!!!

Almost immediately, Athius vanished from sight, causing Karen to land feet first onto the ground.

Karen lifts her head up and she sniffs the air in an attempt to hunt her opponent down.

As Karen crawls along the ground, all of a sudden, something blitz past her.

SCHOOM!!!!

Karen: GROAR!!!! RRR RR!!!

Karen roars out in agony as she felt something struck her, knocking her down.

Karen immediately morphs back into her original form just as Athius halts in front of him.

This time, Athius now resembles a blue humanoid velociraptor with sharp talons and wheels on his feet along with a helmet like visor on his face.

Athius is now in the form of XLR8!

Athius mockingly questions Karen.

Athius: What's wrong? Too fast for ya?

Karen's mouth twisted into a smirk and she said.

Karen: Hardly.

Karen's legs suddenly morphs into two feline paws and without warning, she sped towards Athius.

SCHOOM!!!! BOK!!!

Athius: Argh!!!!

Athius screams out as he felt something strike him, knocking him backwards.

Athius halts himself in midfall and he sprints forward.

SCHOOM!!!!

Karen narrows her eyes and she sprints towards Athius.

SCHOOM!!!!

SCHOOM!!!! SCHOOM!!!! SCHOOM!!!!

Both Kevin and Ben stares at the scene wide eye as they watches two blue streaks striking into each other.

Karen morphs her arms into that of Swampfire and she launches a couple of fireballs towards Athius.

FWOOM!!!! FWOOM!!!

Athius swerves across the groud, dodging the flames with his speed.

SCHOOM!!! SCHOOM!!!

Athius narrows his eyes as he launches himself forward, slamming body first right into Karen.

BAM!!!!

Karen: Argh!!!!

Athius grabs onto Karen as he throws her forward, slamming her right into a boulder.

BOOM!!!!

Athius swerves back and he taps his Omnitrix symbol on his chest.

BOOM!!!

Almost immediately, Athius has transformed into a short stubby white alien with an enlarged head.

Athius is now in the form of Echo Echo!

Athius brandishes his rifle and he began duplicating himself, creating several perfect clones of himself.

VOOM!!! VOOM!!! VOOM!!!

Karen grits her teeth as she watches the Echo Echoes surround her before cursing to herself.

Karen: Shit!

One of the Echo Echo clones said to her.

Athius: It's over.

Almost immediately, all the Echo Echos began opening fire at her.

BIUM!!!!

The Echo Echos widens their eyes in horror as Karen suddenly morphs into a massive humongous creature.

The creature is a large dinosaur like sapien with human-like features on it.

Karen has morphed herself into Humongosaur!

Karen growls as she swung her arms, smacking the Echo Echos back.

SMACK!!!!

The Echo Echo were sent flying as Karen threw her punches.

One of the clones inhales a gust of breath before exhaling out a huge soundwave towards her.

Athius: AAHHHHHH!!!!!

Karen grits her teeth as she felt the soundwave striking her, causing her to weaken.

However, the fight is still far from over.

Karen immediately morphs herself again, this time transforming into a larger and armoured version of Humongosaur.

Karen has transformed into Ultimate Humongosaur!

Karen swung her arms, smacking right into the Echo Echos, sending them flying backwards.

Athius: Whoa!!!

Karen morphs her arms into massive missile launchers and she opens fire, launching a barrage of missiles towards the Echo Echos.

KABOOM!!!!!

A massive explosion rings across the battlefield as Karen unleashes her barrage of missiles.

As soon as she's finished, Karen slowly morphs back into her original form and she smirks.

Karen: Done already?

However, it would take more than that to beat Athius.

Without warning, several blue discs shot out of the smoke, speeding towards Karen.

Karen widens her eyes in shock as the discs floats around her, lavitating.

As sweat began pouring down from Karen's forehead, the discs suddenly began emitting out a loud deafening sonicwave.

EEEEEEEE!!!!!!

Karen: Argh!!!!

Karen screams out in agony as she covers her ears, trying to cover up the noise.

As Karen kneels onto the ground, Athius steps out in the form of Ultimate Echo Echo.

Athius looks down and he said.

Athius: Give up.

However, Karen's entire body suddenly turns transparent, causing the sonicwaves to fly right through her.

The sonicwaves struck the discs, causing them to explode.

KABOOM!!!!

As Athius widens his eyes in shock, Karen suddenly moves in front of him and she swung up her leg, striking him in between in legs.

VOP!!!!

Athius: Argh!!!

Athius cries out in pain as he felt a sharp pain in his groin.

Realizing her advantage, Karen quickly touches him, allowing her to absorb Ultimate Echo Echo abilites.

VOOM!!! VOOM!!!!

Karen then stood back and she places her hands out, causing several discs to fly out from her back.

Karen aims the discs towards Athius and she activates them, causing them to emit a loud shriek.

EEEEEEE!!!!!

Athius: Argh!!!!

Athius screams out as the sonicwaves struck him, causing his entire body to weaken.

However, Athius taps onto his Omnitrix symbol on his chest, causing him to transform once again.

BOOM!!!!

As Athius transforms, all of a sudden, several glops of goop suddenly flew across the air, striking the discs.

GLOP!!! GLOP!!!

Karen widens her eyes in shock before a glop of goop struck her.

Karen: AHHHH!!!! EW EW EW!!

Karen cries out in disgust as she swung her hands, sweeping out the goop off her body.

Athius hovers above her, now in the form of a huge muscular red humanoid with four arms along with four insectoid eyes and two pair of wings sprouted on his back along with a stinger.

Athius is now in the form of Stinkarms!

Athius swoops down and he throws a punch.

BAM!!!

Karen grunts as she was sent tumbling back.

Athius flies forward and he grabs her by her leg before throwing her onto a rock.

BANG!!!!

Karen: Ahhhh!!!!

Karen screams out as she slams bodyfirst onto the rock before collapsing onto the ground.

Athius flies down and he taps onto his Omnitrix symbol, transforming him.

Athius morphs into a huge towering humanoid with red, blue and white skin while two horns sprouted on his head.

Athius is now Ultimate Way Big!

Athius places his hands together and he loudly declares.

Athius: It's over!

ZSSSSSSTTTT!!!!

Athius narrows his eyes as he unleashes a powerful cosmic energy blast towards Karen.

However, Karen still has one more trick up her sleeve.

Karen immediately morphs her entire body, shifting herself into the form of a black humanoid.

Karen is now in the form of Alien X!

Karen places her arms upwards and she swung her arms, rotating in a clockwise direction before releasing a powerful wave towards Athius.

Almost immediately, the blast halts in midair before flying back into Athius's hands.

SCHOOM!!!!

Athius widens his eyes in horror as he stares at his hands in shock.

Just then, his Omnitrix immediately beeps red, causing him to revert back into his original form.

SCHOOOM!!!

Athius stares at his watch, dumbfounded.

With the power needed for the Fusion and the Ultimate forms taking a toll on the Omnitrix, Athius is now unable to access his alien forms for the next twenty minutes.

Before Athius could even move, all of a sudden, something struck onto him by the back, causing him to scream out in pain.

BOK!!!!

Athius: Argh!!!

SLAM!!!

Athius falls face flat onto the ground just as Karen stares down at him.

Karen smiles and she declares.

Karen: I win.

CLAP! CLAP! CLAP!

Both Karen and Athius turns just as Ben applauded the two.

Ben complimented.

Ben: Great fight you two. You have proven yourself today Karen.

Karen blushes and she thanked Ben for his compliment.

Karen: Thanks.

Ben turns to Athius and he said to him optimistically.

Ben: Hey cheer up Athius. With a little hard work, you can beat her in no time.

Athius nods in understanding, accepting the fact that he has to train harder.

Ben then happily stood up and he questions

Ben: Now lady and gentlemen, who's ready for Mr. Smoothies?

KO!

The winner is

Karen

Advantages and disadvantages

Athius

Stronger

Tougher

Inferior in martial arts

Ultimate forms and Fusions takes a toll on his Omnitrix

Transformations have limits

Karen

Faster

Better martial arts skills

Better defenses

Able to morph into any alien without limit

Physically Weaker

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