The Gwens and Kirby find Shadow, who was in Chaos Island, completing the challenge acts.
"For some reason, this one portal needs four keys." Shadow said thoughtfully.
The three hedgehogs and a cute alien look at each other before they head downa creepy tunnel.
"Can I fight this time?" Classic Gwen asked.
"No." Shadow shook his head. "I'm gonna protect both of you."
Classic Gwen groans and rushes off.
"Kirby, please follow little me." Gwen said.
Kirby nods with a splutter before he rushes off after Classic Gwen, panting. Shadow and Gwen nod to each other before they enter inside and saw the scepter glowing as the purple goo suddenly spreads aND Gwen gulps at this.
Shadow glares at the scepter.
"What is this a seal of some sorts?" he asked with wonder.
"Creepy..." Gwen commented.
Just then, a bunch of minions tries to attack them but Gwen leaps at them and cuts the two of them multiple times with her sword and Shadow attacks some then they tosses Chaos Spears at the rest. A figure rises out from the ground and snatches Gwen to their side. She yelps as the figure tries to kill Shadow by firing a rainbow beam. Shadow heard her yelp and immediately dodged it and faced his enemy. A rainbow beam comes back to their clawed hand to reveal... Mephiles.
"I will defeat you then restore myself to the timeline." Mephiles declared.
The ground beneath them became all gooey as Gwen had trouble moving.
Mephiles tries to kill Shadow who dodges the beam as he went around.
"Welcome Shadow... to the Ultimate Game of Shadow Tag!" he laughed.
Shadow performs the Doom Morph and rushes into Mephiles, knocking him down.
"I owe much to you, Shadow and Gweny." he said, going underground.
"Don't talk to Gwen like that!" Shadow growled angrily.
Soon Mephiles made clones of himself as they all send down some pilars. The real one had Gwen in his grasp.
"Shadow!" she screamed.
"She belongs to me. She'll be safe under my care." Mephiles said, stroking her cheek, much to her dismay.
"That's my line! And don't touch her!" Shadow growled, dodging the pillars then used Doom Morph to climb up a purple goo pillar then homing attacked the clones.
Gwen kicks Mephiles who had a strong grip.
"I might consider sparing you for Gwen's sake." Mephiles said, staring at Gwen.
"Don't do me any favours." Shadow stated as he became a monster, going underground with Gwen.
"Plus, I don't know you! How'd you know about me?!" Gwen added, feeling creeped out.
Shadow uses Doom Morph again and attacks Mephiles from behind when he rose. This went on but Gwen slashed his arm with her katana.
"Enough!" she said and stood back to back with Shadow.
"This is the end." Mephiles declared, making many clones to surround them as they tossed spears.
"Chaos Control!" Shadow and Gwen yelled in unison then homing attacked some then punched one then Gwen kicked another as they threw Chaos Spears at them.
The real one looks around before they reappear and kick him.
"AHH!" he screamed in pain, feeling himself about to fade away. "No...! I want to exist...!"
Mephiles sends his minions with his last attempt to defeat Shadow and take away Gwen with him.
Gwen kicks one then leaps into Shadow's hands as he swings her towards Mephiles as he attacks the minions. Gwen uppercuts Mephiles in the chin and roundhouse kicks him away.
Some more minions came out as Gwen summons her bow and arrow from her ruby and shoots them while Shadow throws Chaos Spears at them then uses Doom Morph. Gwen rushed over with her ice sword raised.
"HAAA!" she screamed, slashing him a few times with her ice sword then Shadow performed a Doom Blast, an extended version of that then kicked him to a wall causing dust to shoot out then he slamed him down creating a crater.
Mephiles then disappeared into a scepter, completely defeated.
"There is no future for you. Ever." Shadow stated and walked off as Gwen looked at the scepter for a moment before following Shadow.
They walk out out of the door after taking down Mephiles.
"I'll go get classic me." Gwen said before rocket roller skating off before thinking back at Mephiles they fought. "I got a weird feeling I've met him before..."
Meanwhile, Classic Gwen and Kirby speeds up around the White Space and sees Rouge.
"Wow! You must be the younger Gwen with Kirby." Rouge said as she blushed a bit and then shook it off.
"Um.. Hi." Classic Gwen greeted, blushing a bit while holding Kirby. She got confused at the sudden shyness. Was she into girls? She never got attracted to one before.
"If you're looking for Shadow, he's somewhere." Rouge said.
"Um.. I'm actually looking for my brother." Classic Gwen answered.
"Sure thing, kiddo... I didn't try to bomb him or anything..." Rouge sweatdropped nervously before sighing in defeat in seeing Classic Gwen raise her eyebrow. "Okay, fine I did. It was more of a test to see if he was actually Sonic, I meant no harm."
"I can forgive you." Classic Gwen said as Rogue sighed in relief, wiping her face.
Classic Gwen nodded to Rouge before rushing off. Eventually, Classic Sonic spots Classic Gwen who waves. They soon spin dash around Water Palace then Classic Gwen slashes a robo knight then bounces off Egg Fliers. Kirby held on for dear life.
"Hang on, little buddy!" she assured him.
They soon spin something, making bubbles.
"Cool!" Classic Gwen said in awe as they bouced off the bubbles then slid down on water. "This reminds me of Hydro City!" she cheered, having a blast.
Kirby cheered as they keep on running around.
Meanwhile, Sonic boosts across the water, homing attacking some Badniks.
"Gotta go fast!" Sonic said and saw them in the background.
Later, they enter Crisis City as Classic Sonic and Classic Gwen had trouble dodging flaming lava monsters at one point the sign went flying.
"Oh, come on!" Classic Gwen screamed in frustration, seeing that Black Doom's Eye was following them, mainly Classic Gwen.
They chase after it, dodging huge gaps. At one point, Kirby got lost so Classic Gwen had to skate back and get the traumatized little alien.
Sonic was riding on a board across this place.
"This feels familiar." he said to himself.
Later, they freed Blaze. Blaze blushed to see Classic Gwen, finding her cute.
"Thanks, you two. I wish I didn't need your help. Also you seem less spikey. " Blaze said as Classic Gwen blushed hard.
"Oh, God. Am I bisexual?" Classic Gwen thought to herself. Kirby looks at Blaze and smiles, waving at her.
Classic Sonic rolled his eyes at his sister's shyness around girls.
Meanwhile, Sonic finds Silver.
"Hey, Sonic. Is it you or a evil clone?" Silver asked as Gwen arrived. "Gwen?" he blushed.
"Yep, it's her. Now let's do this. Winner gets the emerald." Sonic declared.
"You're on!" Silver said in determination, liking the challenge.
They soon rush though Crisis City as Silver tosses cars at them, but the hedgehogs smirk as they leap and hit them with homing attacks then hit Silver.
"Ow!" Silver groaned in pain.
"Sorry!" Gwen apologized.
They boost around then homing attack the cars as Gwen used her whip to slam Silver down who grunts then lifts himself up and flies off. Sonic and Gwensoon ran up a hill of cars and homing attacks Silver. Soon enough, Silver makes a huge ball of stuff he brought during the race.
"Meteor Smash!" he yelled.
"Hey!" the hedgehog siblings exclaimed and then homing attacked Silver as the ball crushed him, defeating him.
"Silver?" Sonic asked with concern as they approached down Silver
"I'm good." Silver groaned out, giving him the Chaos Emerald.
"Good. I gotta go find Shadow." Gwen said and then skated past Blaze who smiled.
Later, Classic Gwen was playing a pinball game with Classic Sonic. Classic Gwen was winning as Kirby cheered her on.
"I wonder how this even got here." Classic Gwen wondered when Gwen skated by, grabbing her counterpart who yelped and Kirby.
Meanwhile...
"Wow! We're besties! So cool!" Classic Amy said in awe.
"I know! It's nice to meet you, younger Miss Amy." Cream greeted.
Amy smiled at the sight but became worried about Classic Gwen as it seemed Black Doom had a hold of her.
Meanwhile, the Gwens were running back to find Shadow, holding Kirby when Doom's Eye, projecting Black Doom appeared in front to Gerald and Maria. Shadow got infront of them protectively. Kirby looked scared.
"Don't be frightened!" Gerald assured his granddaughter.
"The promised time is nigh upon us, Shadow. Soon, you will be mine along with you two." Black Doom promised, facing Shadow then to the Gwens and Kirby.
"Shadow and Gwens will never serve you! He's nothing like you!" Maria glared.
"Gerald may have given him this unassuming form, but the blood of the Black Arms flows in his veins. He is a warrior! A destroyer!" Black Doom continued.
"Yes - the warrior that will destroy you!" Shadow corrected him.
This made Black Doom cackle.
"I have learned from our last encounter. There will be no mistakes this time. Struggle all you want. You will be mine."
"Professor... what do you think he means he "learned from our last encounter"?" Shadow asked.
"I surmise you defeated him some point in the future. He has grown a new body and used the nebulous nature of time in White Space to accelerate his plans for revenge." Gerald explained.
Shadow clenches his fist in anger as Black Arms energy begins to gather around him.
"He's right. No more mistakes. This time, I will crush every last one of them!"
"Shadow, no!" Gwen gasped.
Maria grabs Shadow's hands to get his attention.
"Maria?" Shadow questioned.
"It breaks my heart to see you so full of anger. This isn't who you are. Do you know why I named you "Shadow?" Because without light there's only darkness, but a shadow will show where to find the light. Do you understand? I don't want you to be driven by darkness. I want you to be happy. Stand in the light with peace in your heart."
Sunlight shines as Shadow relents, touched by Maria's speech.
"I don't think I feel Black Doom anymore... Thanks." Classic Gwen said, hugging Maria who smiled and hugged back.
"I think I saw your brother race off with Shadow. It's nice to know Shadow made new friends." Maria said.
Meanwhile, Classic Sonic and Sonic ran though Rooftop City as Classic Sonic spin dashed around on the inside then made his way up to the clock and even entered flying battery zone before making it out.
Sonic boosts around knocking the Badniks left and right and smirks. Soon, Vector was released.
"Thanks, Sonic. I got a hunch someone or something is controlling that monster." Vector said in appreciation.
Later, Sonic and Classic Sonic enter Planet Wisp. Sonic performs homing attacks on some Egg Pawns then runs up some bridges and platforms. At one point, the Sonics had to do challenge acts like Blaze helping Sonic across Crisis City. Classic Sonic going up against Blaze.
Soon the Emerald was restored.
"Dude! There's the emerald." Sonic said as he and Classic Sonic ran but Sonic performs an air boost and catches the Emerald.
"Pretty slick move, huh?" Sonic asked as he flipped the Emerald up and down.
Classic Sonic gives a thumbs up before the ground shook a bit.
Meanwhile, Shadow, Kirby and the Gwens find the fifth and final relic.
"The final relic!" Classic Gwen exclaimed.
"No matter what happens, stay strong." Shadow said as Classic Gwen shook up and Gwen nodded, looking tense.
Shadow approaches a relic. It scans his body before absorbing aDoom Gearfrom him. The gear activates the relic, which shatters and unleashes Black Arms energy. Shadow ends up absorbing the energy and contorts in pain.
"No..." he groaned."No..."
He falls to the ground, reaching out as the wings start growing from his back. He contorts in pain as the wings continue growing. He lets out a cry as the wings unfurl from his back, before he levitates and flies around with them. Once he lands, his eyes widens in horror.
"Gwen!" he screamed to see the Gwens holding their heads in pain.
Upon Shadow's manifestation of the Doom Wing, the Black Moon surges in energy as it reaches its full potential. The symbol then launches a beam to the sky, breaking the dimension and causing the Doom Zone to combine with White Space.
"Well, this is it... Bye, Shadow... Leave us." Gwen said sadly, feeling weak in the head.
"No, never!" Shadow shook his head and grabbed them and flew off as they hold onto him, blushing.
Holding onto the Gwens, Shadow uses the Doom Wing to fly to Maria and Gerald. As he lands and places the Gwens down, he expels his heightened power as Black Doom appears.
"You cannot deny me, Shadow. You are finally complete and so are you two. Come. Face me. I shall claim you—mind, body and soul—and become the perfect being." Black Doom said.
"Never!" Gwen shouted, trying to stay in control but felt real dizzy.
Classic Gwen was starting to fall under his control, but Maria ran to the three of them.
"Gwens, please don't give up! I know we just met but... you're like sisters to me." Maria pleaded with hope and encouragement.
Shadow turns to them and Gerald.
"It is time." he said.
"I am sorry I put you three on this path." Gerald said in guilt.
"And my brothers and our friends." Gwen added.
"But I'm proud of how you have walked it." Gerald continued with a smile. "I believe in you, son. And to you as well, Gwens."
"Honestly, none of this would have happened if I'm not really the ultimate lifeform... I think it's Gwen. She's been doing Maria's wish the whole time." Shadow said fondly.
Gwen had a flashback.
Super Sonic, Super Shadow and Super Gwen was fighting the Biolizard.
"I think I know who the ultimate lifeform is. It's you and your brother." Super Shadow said as Super Gwen blushed.
"You fought Robotnik multiple times, saved your brother." Shadow said and hugged them as they unleashed a glow and snap out of his power.
"Thanks, Shadow!" Gwen smiled happily.
"Thanks to Gwen... I'm letting go of that destructive anger." Shadow said.
"Shadow...!" Maria said worriedly.
"It's alright, Maria." Shadow assured her. "But I will continue to fight."
White Space trembles. Maria falls, but Shadow helps her up and holds her hands.
"Fight... with your wish in my heart. Your wish for everyone to have a chance to be happy." Shadow said and then actually smiled as the Gwens smiled at that.
Maria smiles back at him before Shadow lets go of her hands, and Classic Gwen hugs Maria, who hugs back. Then Shadow grabs the Gwens' hand and flies off to face Black Doom.
They head off to Radical Highway
"My brother was here." Gwen said.
They speed off destroying the Black Arms that are in their way as they try and shoot or attack them, but Gwen blocks one and stabs one a bunch of times as Classic Gwen notices the one eye alien and grabs it and slams it against another Black Arms. Shadow tossed Doom Spears at some.
Meanwhile, Sonic rushes though Tropical Resort using the Burst Wisp to get around, though the background was red.
"Huh, wonder why this area is red?" he asked before pelting Egg Pawns with homing attacks.
Classic Sonic looks on in awe and tries the Burst Wisp.
"We're so winning this competition!" Sonic thought with a grin.
Shadow and the Gwens keep going though radical highway and smirk.
"As long as we don't lose control, we'll be fine!" Gwen ssid.
Meanwhile, Rouge flew up to the top of Sunset Heights and hid. She sees two people nearby and her eyes widens.
"So that's Maria." she said to herself thoughtfully, looking at the blonde little girl and the doctor in a lab coat.
She got ready just in case something happened to them, just as she promised to Shadow.
Meanwhile...
"So what happened?" Shadow asked her.
"Well, I ran into Silver, and Sonic and I beat him." Gwen explained.
"So, about the Super Emeralds?" Shadow asked, destroying the robots.
"It's a long story. Basically Sonic, Tails and I went to Angel Island in our Super Forms, and Knuckles knocked it out of us then he ran off, taking me along." Classic Gwen explained her story. "Sonic soon discovered the Emerald Shrine and fixed the Super Emeralds, which allowed us to go Hyper. We so kicked his butt! Then afterwards we broke it... then Eggman teamed up with Fang and Knuckles, and they kidnapped me... again!" she huffed in annoyance before continuing. "Then, Sonic and Tails saved me then we saved Knuckles, then we went to Angel Island. We even teamed up with the Chaotix for the first time. Knuckles, Espio and Mighty was hard to deal with since they fought nearly the whole time."
Gwen slashes her way though some Black Arms and finishes Classic Gwen's story.
"Then Eggman tricked Sonic into wearing slow shoes."
This made Shadow acutally laugh at that part about Sonic.
"Oh, then we teamed up with Tails, Knuckles and Amy and entered some Grand Prix. Metal Knuckles captured me, but Knuckles destroyed him." Gwen said.
"Interesting." Shadow said, punching the Black Arms then grabbing them and flying them around.
"Then Eggman tried using a water god named Chaos to rule the world, but we stopped him." Gwen continued as they land on a platform.
"Story time is over." Shadow declared, facing ahead.
Meanwhile, Sonic was running around and dodged a missile as he spots the Egg Dragoon. Sonic rushes around, getting some Rings on the way as he leaps around, dodging missiles. Soon grind railing and leaps off and hits him with a homing attack. This went on a few times before Eggman tries shooting ice at Sonic, who jumps over the ice and then Eggman traps him between two walls.
"Time for a change of pace!" Eggman said as Sonic does wall jumps then hits him with a homing attack.
He flew off as Sonic gives chase, dodging missiles again. Soon Sonic was sky diving and boosts into Eggman's cockpit. Hesoon landed. He looks up to see Tails flying with Classic Tails, who held Classic Sonic.
"I was supposed to beat you this time!" Eggman whined.
"I'm sorry. I didn't get that memo. I beat you every time." Sonic said as Classic Sonic snickered and giggled. "I'm not joking, we beat this guy everytime!"
"Stopping Eggman is good and all, but that Time Monster and Black Doom are the problem. Maybe we can call a truce and work together to save the Gwens?" Tails asked as suddenly the Time Eater scooped up Eggman and went away.
Everyone looked up as the portal closed.
"Aww, man! This is getting serious!" Classic Tails said, looking down.
Meanwhile, Shadow and the Gwens glare as Black Doom arrived.
"Hello... Shadow and slaves." Black Doom greeted them.
The trio got ready, ready for one final showdown.
End of chapter. Next time, Shadow and Gwens vs Black Doom!
A/N: In Sonic Adventure 2, Shadow actually called Sonic the True Ultimate Lifeform.