Author's note: I don't own Yu-Gi-Oh or Transformers. I'm just borrowing them for a while. So don't get any ideas. I may also use another author's characters without knowing, so please let me know if I've stepped on someone's toes, ok?

I Think We Took A Wrong Turn...

Dimensions are funny things. Like shapeless masses they expand and contract, bulging and flattening, never keeping the same shape or size. When two dimensions collide, portals open between them, allowing travel back and forth if the races that encounter them know how. Other peoples are pulled in by close proximity to the gateway. This happens completely at random, as several unfortunate people were about to find out...

Yugi Moto was talking to Joey, Tristan, and his other friends on the bridge of Seto Kaiba's blimp. They were heading for an island to finish the finals of the Battle City Duel Monsters tournament. Kaiba was standing a few feet away, his back to them. His little brother Mokuba was occasionally contributing to the conversation.

"We are approaching the ocean, Mister Kaiba," the pilot reported.

"Good," was the chill response.

"Ya could try bein' a little nicer, Mr. Billionaire," Joey snapped at him.

"Was I talking to you, mutt?"

"Why, you..."

"Calm down, Joey," Yugi interrupted, standing between the two. "Don't start another fight."

Abruptly, the blimp rocked slightly.

"What was that?" Kaiba demanded.

"I'm not sure, Mister Kaiba. The sensors can't find anything."

The blimp rocked again. Then the air seemed to explode.

Kaiba, Yugi, Joey, Mokuba, Duke Devlin, and Ishizu felt like they were being pulled apart. A strange wind screamed around them. Flashes of color threatened to blind them. What little they could see resembled a strange tunnel of grey lightning, flashing around them. It twisted and kinked in knots, slamming them about like leaves in a hurricane. Yugi clutched his Millennium Puzzle tightly, feeling Yami clinging to the door of his soul room for dear life. The ancient spirit demanded to know what was going on. Yugi had no idea, and said so.

The wind ripped at their hair and clothing, burning their eyes. Yugi could hear Mokuba screaming, and turned to see Kaiba gripping his little brother tightly.

A bolt of the strange grey lightning sizzled nearby, nearly striking Duke. The creator of Dungeon Dice Monsters swerved to avoid it. Ishizu careened past, bouncing hard of the wall of the tunnel. Then they saw a glimmer of light ahead. The tunnel gave one last furious convulsion and spit them out onto a hard surface.

Groaning, they pushed themselves up onto all fours. Yami materialized in spirit form beside Yugi.

"Aibou, are you all right?"

"Yes, I think." Yugi looked around. "Where are we?"

Everyone managed to climb back to their feet. They looked around, trying to figure out their location.

"Uhm... I don't think we're in Japan anymore," Joey commented. "Not even Kaiba's fancy shmancy buildings look like this."

They were in a huge room, obviously sized for something huge. A deactivated screen occupied one wall, above a console. The console and the chair in front of it were over fifty feet high. The room was made of a strange metal, and was lit by lights in a ceiling over 100 feet up. A strange hanging covered one wall. Another held what could be called a hunting trophy. It was the mounted head of a scaled beast, vaguely horse-shaped, but with greenish scales, red eyes, curved horns stabbing outward from its forehead, a spike on its nose, and a maw full of sharp teeth. The canine teeth were elongated fangs. The beast was obviously a carnivore. Other furniture, also sized for someone of great size, filled the room.

Then they felt eyes on them.

Kaiba turned, looking for the source. He scanned the room at normal human-height before remembering the size of the furniture and looking up.

He turned white, eyes widening so fast Yugi thought they'd pop out of his head. His jaw worked, but no sound came out. One trembling hand came up to point at something. Everyone turned to look.

A huge creature stood in a doorway, watching them silently.

The creature was humanoid in shape, but much, much bigger, covered in dully gleaming metal armor. In color, it was mainly grey and dark blue, with red on its shoulders, forearms, torso, and spots on its legs, and white on its upper arms. Its feet were black. Long silver hair hung down its back. Narrow emerald-green eyes studied them carefully, as if trying to determine what they were. On its chest was a red mark, shaped like a face, on a blue triangle and given wings. It was slender of build, but still gave off the feel of raw power, and the distinct feel of masculinity.

Yugi's jaw dropped. Even Yami, and ancient Egyptian pharaoh and used to huge creatures, was taken by surprise. None of them had ever seen anything like it before.

"Who are you?" the creature asked in a deep, male voice, narrowing its- his- eyes even more. "Why are you here?"

"We don't know how we got here, or even where we are," Yugi managed to reply. "My name is Yugi Moto. These are my friends Seto Kaiba, his brother Mokuba, Joey Wheeler, Duke Devlin, and Ishizu Ishtar."

"I am called Ultra Rodimus. You're in my personal quarters in Iacon City, on the north continent of the planet Cybertron. You are a long way from home, humans." Those green eyes fixed on something beside Yugi. "You failed to introduce your friend."

"You can see me?" Yami asked, stunned.

"I can. Who are you."

"My name is Yami. I am the spirit of the Millennium Puzzle. 5,000 years ago I ruled Egypt as Pharaoh. Now I am a spirit."

"A spirit. I know of spirits. I've faced them before. They usually mean nothing good. The last one I faced was the ghost of the Decepticon Starscream. He tried to destroy Cybertron, and nearly succeeded in reviving our greatest enemy, Unicron." Ultra Rodimus growled under his breath, his hackles, if he had any, bristling. "The only reason we defeated them was because Starscream betrayed Unicron, and gave us the chance to defeat Unicron again."

"You mean we're on another planet?" Mokuba's voice cracked.

"You are. This world is called Cybertron."

"And what are you?" Kaiba had finally found his voice.

Ultra Rodimus's lips twitched into a smile. "I am a Transformer, a sentient robot."

"Machines are merely machines. They cannot become sentient," Kaiba protested. " This is a trick!"

Ultra Rodimus's eyes flashed, glowing with internal fires. His lips peeled back from his teeth. He was literally growling with rage.

"You DARE call me a liar?" His voice was thunderous, threatening to deafen the humans. There was fury in his voice. "You DARE imply that I might not be telling the truth?"

He was expressing such rage that none of the humans could deny that he had real feelings. When Kaiba attempted to placate him, Ultra Rodimus dug h9s fingers into his side and tore his chest open.

The hum of machinery instantly picked up. Under the steel plate was a network of sensors, a tangle of fluid lines, banks of chips and circuitry, and two fuel pumps, beating like hearts. Power surged along conduits, spreading through his entire body. Fluid lines pulsed as fluids were pumped through them. The circuits and sensor mesh formed an elaborate, sensitive system that copied a human nervous system. That meant he had a sense of touch as sensitive as any human's. His body was packed with complex machinery.

"Now do you believe that I'm telling the truth?" Ultra Rodimus hissed. "Do you still think I'm joking?"

"Uhm, no..."

"Good." Ultra Rodimus resealed his chestplate and crossed his massive arms over his chest.

"So, if you're really alien, we're really on another planet?" Mokuba asked slowly.

"That's right. Now let's get you bunch out of my quarters before the science crew comes barging in."

Ultra Rodimus scooped the group into his hands and carried them down to Medbay. Instantly, two medics and a scientist swarmed them.

"There's a dimensional portal in your quarters, right here." Perceptor pointed.

"Will we be able to send them home?" Ultra Rodimus wanted to know.

"Not until we know more about the breach. That means you'll have to move into the safe quarters."

Ultra Rodimus groaned.

"Safe quarters?" Yugi repeated.

"Underground. He's the current Prime, which means he's our commander. You could say he's our ruler. He has two sets of quarters, the ones he normally occupies, and a reinforced underground set for use in sieges. He hates not being able to see the sky, so he's never down there very often. Now he won't have much of a choice."

Ultra Rodimus looked over to where Kaiba and Perceptor were engaged in a conversation, spouting tech-talk left, right, and center. "Looks like Professor Perceptor found another techno-geek to chat with."

Yami took control of Yugi's body, explained what they were doing to Ultra Rodimus, and wandered over to Ishizu. "How about a practice duel?"

She agreed. Both powered up their duel disks and began. Ultra Rodimus watched with interest.

Yami, of course, won.

"That looks like fun," Ultra Rodimus commented. "Could you teach me how to play?"

Perceptor offered to enlarge the cards and construct a duel disk for Ultra Rodimus. The duelists let Perceptor enlarge their cards. Kaiba was reluctant to give up control of the only three Blue-Eyes White Dragons in existence, but Mokuba talked him into it. Yami and Yugi began teaching the Prime the rules and methods of play in Duel Monsters. Ultra Rodimus proved a fast learner. He picked up the rules quickly. Soon he was on par with Kaiba, Yami, and Yugi.

"You're good at this."

With Yami's help, Ultra Rodimus created his own Duel Monsters cards, based on Cybertron's own creatures, deities, and mythical beasts. Yami helped decide their power levels, special abilities, and weaknesses. Once that was done, Ultra Rodimus presented each of the duelists with a special card.

Kaiba looked at his new card. It showed a crimson-scaled, cobra-like serpent, hood spread, fangs bared, ready to strike. It was a scarlet dhast, Cybertron's deadliest serpent. It had 2700 attack points, and the ability to destroy any monster it bit, without activating its victims' special abilities. Ishizu had a razorbird, a vicious four-legged steel bird with razor-sharp wings and power over wind. It had 2400 attack points and 3500 defense points. When it wrapped its steel wings around itself it was practically invincible. Joey's was a relli, a three-headed water snake with lethal venom. It had 2100 attack points and 2500 defense points, and could attack multiple times in one turn.

"Thanks, big guy!" Yugi hugged his new card to his chest. It was a dragon with four heads, three eyes per head, six legs, two tails with four tips each, and eight wings. It was a mythical creature called a space dragon, a monster with the power to destroy entire stars. It had 3600 attack points, 2700 defense points, and its special ability allowed it to be summoned to the field without needing any tribute.

"You are welcome. I think Perceptor finally knows how to travel through the dimensional breach. Let's go."

"You're coming?"

"This tournament sounds interesting. I want to watch."

They went through the breach.

Ultra Rodimus, now only six feet, seven inches tall but still in his natural form, metal, weapons, and all, exchanged hostile looks with Marik. The twisted duelist decided that Ultra Rodimus was too tough a nut to crack, and decided to leave him alone. The tall man's eyes expressed his intelligence, and a powerful mind lurking behind those emerald eyes. Marik doubted he'd be able to control the newcomer, and decided not to try. There was raw power hidden in the stranger's slender body.

Tea and Serenity eyed Ultra Rodimus curiously. Yugi explained who he was and why he was there. Tristan stared. Ultra Rodimus was quite a bit taller than he was, and his skin was covered by armor. A long silver braid hung down his back. There was an aura of authority around him. He knew his own power. Not even Kaiba radiated such a feel of leashed strength.

"Mister Kaiba! Something's wrong!"

Kaiba looked at the pilot. "What is it?"

"We're being pulled off course! Systems aren't responding! The auto-pilot is down! There's nothing I can do!"

"Look!" Yugi pointed.

A huge ship of some kind began rising from the waves. The blimp's main viewscreen flashed on. A green-haired kid sneered at them. He introduced himself as Noah. Then the ship pulled the blimp in.

On the ship, the group came across Kaiba's old business partners, the Big Five, Gansley, Crump, Johnson, Nesbitt, and Lector. The big five had been trapped in the virtual world after the incident in which they tried to trap Kaiba in his own computer game. Now they wanted to escape. To do so, they dragged the group into the virtual world, separating them, and began to duel them for control of their bodies.

Yugi and Ultra Rodimus managed to stay together. Gansley, in the form of a monster called Deep Sea Warrior, found them. After looking them over, Gansley decided Ultra Rodimus was out of his experience, and the look in his emerald eyes indicated that he was no stranger to combat. Gansley decided to take on Yugi.

Yami took over their shared body. The duel began. While Ultra Rodimus wasn't taking part, he could help keep Gansley distracted, and taunted Gansley at every opportunity.

"Be silent!" Gansley roared at him.

Ultra Rodimus straightened his back, stared coolly at Gansley, and suggested that Gansley do several highly improbable, athletically difficult, and possibly biologically impractical acts involving his own mother, a few household items, and a dead fish. Gansley seemed to purple with anger.

"Once I'm finished with this weakling, I'll teach you a lesson in respect, you little bastard!" Gansley exploded.

Ultra Rodimus's eyes turned frigid. If any of his Autobots had been there, they would've begun taking bets on how few words it would take Ultra Rodimus to verbally skin Gansley alive. In a voice as chill as outer space, Ultra Rodimus explained in vivid detail exactly what he would do if he ever got his hands on Gansley, naming a variety of ancient Cybertronian torture weapons, a few dull knives, and his bare hands. When he was finished with Gansley, the business goon was shaking in fear.

Yami, who'd been a Pharaoh in ancient Egypt and had thought up some very original torture methods in his time, whistled in amazement at how bloody-minded Ultra Rodimus could be. Ultra Rodimus utterly loathed Gansley. His hands were resting on the broad belt he always wore, made of scaled crimson hide, as if itching to replace it with scaly green fish skin. The look in his emerald eyes was lethal. If looks could kill, Gansley would've been dog food.

All through the duel, Gansley kept shooting terrified glances at the cold-eyed warrior behind Yami. Ultra Rodimus resumed his verbal taunting, keeping Gansley off guard. When Yami finally won the duel, Ultra Rodimus fired one of the missiles hidden in his shoulder armor to make sure Gansley ran. The missiles were small, but they were powerful. A vast crater smoked heavily after the detonation. Then the human, the ancient spirit, and the Cybertronian warrior left.

One by one, they rounded up the rest of the group. The only one missing was Marik, and that was because Noah hadn't known about him. The group were heading toward a large mansion on a hill when the Big Five ambushed them. Yami and Joey went into a five-on-two duel with them. It was a hard match, but they won. Noah banished the Big Five to separate corners of the virtual world and decided to take on Kaiba himself.

The match was long and hard. Noah used Mokuba to keep Kaiba from attacking. Finally, Kaiba launched an attack at Noah's Deck Master, Shinato. Noah only laughed and blew Kaiba's Blue Eyes away.

Noah turned Kiaba and Mokuba to stone. Yami was about to yell at Noah when a deep voice cut him off.

"NOAH!"

Startled, Noah turned to look at the warrior. Ultra Rodimus's eyes were literally glowing with green fire. He was beyond furious.

"You call yourself a duelist, but you're nothing but a helpless little bot! You use tricks to win instead of fighting fair! Even the cursed Decepticons have some honor! You are simply weak!" Ultra Rodimus pointed at Noah. "I challenge you!"

"Accepted."

Ultra Rodimus paced forward. Kaiba's Deck Master, Kaizer Seahorse, followed him.

"I think we need some privacy for our duel."

Two chunks of ground rose into the sky. Ultra Rodimus only laughed.

"I think we need a change of scenery."

The Earth dropped away from them. They were rushing through space, passing stars and planets. Then another planet appeared, rapidly coming closer. It had four huge continents and chains of massive islands. They descended onto one of the continents.

"I did not choose this world!" Noah raged.

"I did." Ultra Rodimus showed his teeth in a fierce grin. "You see, I'm not human. I'm not from anywhere on Earth. I'm from a different world. I'm a living, sentient machine. You're only a pitiful human stuck in a computer. I control this place now. Welcome to my world. Welcome to Cybertron!"

Their surroundings resembled a tropical jungle. Ultra Rodimus hovered above a stretch of water dotted with small islands. Noah, merged with his Deck Master, hovered over a swamp.

"It's my turn." Ultra Rodimus drew a card. "I play this monster in attack mode!"

There was a burst of light under the water, indicating that a monster had appeared there. The surface of the water rippled briefly, then stilled.

"My move now." Noah drew. "I use Reborn the Monster to bring back my Giant Rex!" A dinosaur monster appeared. "Giant Rex, attack!"

The monster roared and lunged. It had barely reached the edge of the water when the water erupted. The Giant Rex screamed.

A beast had it clenched in its powerful jaws. The monster had two heads like those of a crocodile, eight legs armed with scythe-like claws that could gut any enemy with one swipe. Two powerful tails lashed the water into a froth. The beast was mottled shades of blue, grey, and green. It had the Giant Rex by the leg and neck. With one powerful jerk, the beast ripped the Giant Rex in half.

Noah's life points dropped.

"I forgot to mention that Cybertron's creatures are nothing like Earth's," Ultra Rodimus commented. "That's an atul. Good luck trying to beat it."

Noah eventually managed it. Ultra Rodimus chuckled.

"Then try this one! I summon the death eagle, Stratoraptor velox!"

The monster looked like a giant dinosaur covered with feathers and with a beak. Then it reared back and screamed, exposing a row of curved, tearing teeth. Its arms were rather long, ending in three-fingered "hands", each finger terminating in a deeply curved claw. Its hind legs ended in three savage talons. It had 2800 attack points and 3000 defense points.

"Attack his life points directly!"

The death eagle charged. Its huge claws came down in a lethal arc, slashing right through Noah's life points. Noah screamed in pain as those claws scored a direct hit. His life points dropped by 2800 points.

The duel went like that for a while. Noah noticed a hissing sound from behind and turned around to look. A huge crimson cobra loomed over him, tongue flicking out and in. Its hood was spread.

"I didn't summon that," Ultra Rodimus said casually. "That's native to my world. It's a scarlet dhast, Cybertron's most lethal serpent. It spits venom. Its poison is a very powerful acid. No one who gets bitten on hit by sprayed venom ever survives. Only the very brave hunt scarlet dhasts."

"And how do you know?" Noah challenged.

Ultra Rodimus patted his scaled crimson belt. "I'm one of them. This is dhast hide."

Noah shuddered.

Finally, Ultra Rodimus had four monsters out, two weak and two powerful. Noah moved his Deck Master back into play.

Ultra Rodimus roared with laughter.

"What's so funny?" Noah demanded.

"You did exactly what I wanted you to do!"

"And what was that?"

"Play your Deck Master."

"And why did you want me to do that?"

"So I could do this! Activate Solar Snare trap card!"

A trap card activated, snaring Shinato.

"Now all your special abilities are useless. And now to destroy you! I sacrifice all four of my monsters to summon a new monster!"

He played a card.

"Reveal the Hell Gates!"

A green river full of screaming souls appeared. A black boat poled along by a skeleton, Cheron, boatman of the River Styx, floated past. Then Cerberus, the hellhound guarding the Hell Gates, came into view. It snarled but moved aside. The black steel gates opened.

Infernal heat blasted out as if propelled by a cannon. Hair-raising, nerve-shattering screams echoed across the blasted plains of Tartarus.

Something moved.

A hellish howl echoed across the gates. It was the sound of coffins groaning as they opened, the dead moaning, and a deep groan echoing from the bottom of a well all rolled into one sound. Then the owner of the howl appeared.

If someone had taken a four-legged dragon, given it the skull of a Tyrannosaurus rex and the horns of a mountain sheep, then skinned it and removed all its flesh, the result might look something like that monster. It was skeletal. Nothing held its bleached boned together. No flesh hung in tattered strips from its ribcage or stretched between the "fingers" of its wings. Its eyes were balls of blazing red fire in its eye sockets. Its huge jaws revealed a row of tearing teeth, with long fangs in proportion to the rest. A bony tail swished behind it, and bony claws flexed into the ground, tearing clumps of earth out. Its growl came from somewhere in its ribs.

"Behold Akasha, the demon-lord of Hell!"

The monster roared again. Shivers ran up and down everyone's spine.

"Since Akasha is the ruler of Hell, he gains attack points for every monster in our combined graveyards."

Noah watched as Akasha's attack points climbed to over 5000.

"Akasha, attack with Soul-Reaping Slash!"

The demon charged. One huge foreclaw lashed out. Noah let out a shrill scream as those claws tore his Deck Master to ribbons.

"It's over."

Noah was forced to make good on his promise to let them go. The group, including Kaiba and Mokuba, returned to the real world and continued on to the duel tower on Kaiba Corp Island. Ultra Rodimus remained until after the finals were finished, then returned to his own world. He kept his own deck of Duel Monsters cards, and decided to teach other Autobots how to play.

"Do you think we'll ever see him again?" Yugi asked Yami.

The spirit smiled. "Something tells me our paths will cross again, some day."

Yugi smiled. "That's good."

With that, he drifted off to sleep.

Fin.