Authors Note: Hello everyone.

This is a story I've been working on for quite awhile. If you've read my profile page, you would know that Sonic Unleashed is my favorite Sonic game. I loved the gameplay, the story, and the locations of it. To me, this was a relative high point in Modern Sonic.

Now the idea of doing a Unleashed AU had been in the back of my mind for about a year, but it wasn't until October that I really began to develop it. I have an outline for it and so far it's not done yet, but I do know this isn't going to be a short story.

One thing about the schedule for these chapters. I already have the next 2 chapters ready to go, and they will be posted weekly. After those 2 chapters are released, the rest will simply release when they're done.

Also, if you're a fan of The Metallic Replacement, don't worry. As I said in the last chapter I posted to that story, I will be writing both The Metallic Replacement, and The Beast Inside Chapters and will post them when they are done.

Right enough rambling, let's get this story started.

Chapter 1: Awakening.

Space is a relativity big place. Almost endless nothingness at every direction. However, above a certain planet right now, it wasn't as empty as it usually was.

Above the Earth, there were various ships grouped together. They were equipped with various cannons, guns, and some that large armies of robots inside them. Inside the ship leading them, Eggman was laughing as he watched his fleet come together. He was confident that nothing could stop this invasion, not even his arch nemesis.

An alarm suddenly went off, notifying him of an explosion at the front of his ship. Looking towards it, he almost couldn't believe his eyes.

Standing in front of the fire, was Sonic The Hedgehog. Even though Eggman was some distance away, he was staring directly at where Eggman was.

Eggman then began to press multiple buttons. At once, the cannons on the ship turned towards where Sonic was, and hundreds of robots were deployed in front of the hedgehog.

"FIRE!" Eggman yelled, pointing at where the hedgehog was.

The cannons then began to fire. Sonic didn't wait for the cannons to hit him, instead running towards where Eggman was, dodging additional cannon fire as he did so. When he reached the robots, he dodged the first robot in front of him and began to bounce back and forth through the smaller robots like a pinball, destroying them in the process.

A bigger robot then charged towards Sonic who dodged it's fist by sliding under it and he quickly made short work of it.

Seeing how badly things were going, Eggman then pressed another button, lowering him into a controllable robot and jumped towards the hedgehog.

He tried to smash him into the ground, but he effortlessly dodged it, landing on the cockpit window of the robot. He gave the doctor a wave as he did so.

"Why you little..." He said attempting to grab Sonic, but the hedgehog leaped off the window and landed behind him.

"Better watch your language Egghead." Sonic taunted as he dodged another swipe from Eggman's robot.

Deciding he was done playing around, Eggman configured the hands of the robot into machine guns and began to fire at Sonic. The hedgehog dodged the gunfire by running up the wall, the gunfire trailing just behind him.

The machine guns eventually overheated and Eggman switched to the missiles. They flew towards Sonic, who spotted a gap he could run through and he sped up, narrowly avoiding the missiles that blew up behind him just as he ran through the gap.

"Oh no you don't." Eggman said as he shifted one of the mech's hands back to normal before he launched the hand through the gap.

Sonic, running through the gap, took a look back and noticed the hand racing towards him.

"Uh oh." He said as he tried to go faster. But just before he was about to do that, the hand grabbed him and he was pulled back through the gap and back towards Eggman.

Eggman brought the hedgehog close to the cockpit, wearing a grin on his face.

"Looks like I got you now you rat." He said.

Sonic simply smirked at that. "You really think so?"

He then closed his eyes, and much to Eggman's surprise, the seven chaos emeralds suddenly appeared around him.

"What?" he quietly said as he used the other mech's hand to try and grab the emeralds.

Just as he covered his hand on them, both hands blew up from a blast of energy, leaving the mech without arms. Sonic was now floating in the air, his fur now yellow, his quills pointed upward, and with red eyes instead of green.

Sonic then charged through the Mech, blowing a hole through it's torso, though leaving the cockpit where Eggman was untouched.

"Time to go." Eggman said in a panic as he pressed a button that detached the Egg-mobile from the mech and flew away from the now super Sonic.

"Oh no you don't." Sonic said as he flew after Eggman. The doctor tried his best to delay the hedgehog by closing numerous doors behind him, but that only bought him about a second as the hedgehog simply smashed through the doors with his super form.

The chase led out into space, with the ship exploding just behind them. As the pursuit continued, the cannons on the other ships tried to fire at Sonic, but he dodged them and destroyed the ships within seconds.

Regardless, Sonic continued to pursue Eggman, who was going away from the fleet and towards a space station that was domed shaped with a cylindrical shaft pointing downwards towards the earth.

Eggman flew into the station as quickly as he could, stopping the Egg-mobile just as he was inside. This caused him lurch against the control panel, opening the windshield of the small craft and he ended up tumbling out of the vehicle.

Mere seconds later, Sonic came bursting out of the floor, stopping just near the ceiling. He looked down at Eggman, smirking over the fact that he had caught his nemesis.

Eggman backed away towards the wall as the hedgehog slowly lowered himself to the ground. "S-Sonic." he stammered in a panic. "I'm sorry."

The hedgehog's feet touched the floor as Eggman continued to plead, cowering on the floor with his knees bent and his head down. "Really l-look, go easy on me. I'll turn over a new leaf I swear, just give me a chance"

Sonic simply smiled and gave a small chuckle. "Heh, well this is new. Showing remorse, Eggman?" he said to Eggman with a hint of sarcasm. He had heard this from him before, and he knew that Eggman would still go back to trying to take over the world at the end of the day. But he was so super-charged with energy that he didn't even care.

He then turned towards one of the windows that showed the now destroyed fleet. "Gotta say though, you weren't exactly subtle with your whole invasion plan. I mean, a fleet this big is gonna get someones attention, and of course announcing it to everyone in the world. I mean, even for you that's a bit obvious."

He turned his head back toward Eggman and smirked. "Of course if you just played nice I wouldn't have to break your toy's." He continued as he wagged his finger towards Eggman.

Unbeknownst to Sonic however, as he was talking, the doctor had gotten a device out. He was also no longer cowering, but rather, slowly getting up with a grin on his face. Letting out a quiet chuckle at his enemy's obliviousness, he pressed the button on the device. "Gotcha."

Suddenly, around the room, hidden compartments began to open up. "What?" Sonic said as his cockiness disappeared as he watched the room begin to transform around him. Rectangular pillars began to surround Sonic in a circle and rods descended from the ceiling, trapping him within the circle. He tried to flee as the components closed in on him, but whenever he got close to the edge, he was hit by blue energy beams that forced back to the center of the circle. Eventually the beams trapped him in the center, causing him to struggle as he tried to break free from them.

'Damn, that blue energy must be neutralizing my super form's power.' Sonic thought as he tried to break free.

He then heard Eggman laughing and he turned his head towards him. The doctor was now rising on a platform, grinning as he watched the hedgehog struggle against his bonds.

"Did you really think I was going to use that fleet as part of my plan?" Eggman asked as this happened. "That was just to get your attention. My actual plan involves the Chaos Emeralds that you have right now."

Sonic continued to struggle against his bonds. "What are you going to do with them?" he yelled back.

"Oh you'll find out soon enough." Eggman replied as he went to a control panel. "But first, I'll need to extract the emeralds from you."

He pressed a button on the panel and immediately, the rods above Sonic began to crackle with purple lightning. He stopped struggling and stared up at the rods in terror. He knew what was about to happen.

Not a second later, the lightning began to direct itself toward him and begun to shock him. He began to scream in pain as he twitched in the air from the electricity. As he did so, he felt the power of the chaos emeralds begin to slip away from him. He tried his best to resist through the pain, but it was no use. Eventually, the emeralds were torn away from him and he was forced back into his normal form and the seven emeralds hovered around him.

As this was happening, Eggman stared with great glee as he flipped a switch on the control panel. Outside the station, the cylindrical shaft began to unfold and expand into a cannon, not to similar to the one on the ark. As it unfolded, it began to charge with purple energy not to similar to the electricity that was electrocuting Sonic now.

Inside the station, Sonic was in complete agony now. Without the protection of the emeralds, he could now feel every shock that the electricity gave him. He screamed as he glared at Eggman through the pain. Through the pain, he could see the colors of the emeralds dull in color.

Eggman meanwhile, was staring at a progress bar on the control panel with great excitement. The progress bar was filling up quickly, going from 50% to 75% within a few seconds.

"Oh I've waited a long time for this." Eggman said as the progress bar neared it's completion.

Outside the station, the cannon finished forming, now brimming with purple energy that was pointed directly at the Earth.

At the same moment, the progress bar reached 100%.

Grinning madly, Eggman raised his hand above him with a finger extended. "FIRE!" he yelled as he slammed his finger down on a big red button.

The cannon fired all the purple energy that it had built up and it hit the earth below. The beam landed in the ocean, causing a massive wave to form and a shockwave that rippled across the land. However, the beam had continued through the water and penetrated itself down to the earths core.

However, that wasn't the only effect the beam had on the planet. Around the world, the crust began to split and crack into pieces, causing earthquakes around the world and magma to spew out from the cracks. Magma wasn't the only thing that was emerging however, as dark purple tentacles emerged along with the magma, pushing and weaving over the pieces of the planets.

Eggman watched all of this, completely in awe of it. He was so absorbed by the sight that he didn't notice what was happening to Sonic. By then, the hedgehog had collapsed onto the floor from the pain of the electricity. However, he was still struggling to get up despite the pain.

However, as he did that, a new feeling suddenly came over him. His insides felt they were shifting inside him and his skin felt itchy.

'What's...happening...to me?' He managed to think through the pain.

Because of the combined pain from the electricity and whatever he was feeling now, he was forced to shut his eyes. As such, he didn't see the changes that were happening to him.

His blur fur began to lengthen and turn a dark blue color, even covering his arms. He then felt the muscles in his arms convulsing, causing him to groan as a result. As his arm began to bulk in muscle, his groan turned into a growl. His gloves began to strain against the growing arm, eventually ripping them apart, revealing a large paw like hand that soon gained black pads on both his palms and fingertips. His fingers curled as his nails became long, black claws, scratching the floor in the process.

Across his body, he felt his bones break and expand as they began to fit his new form better, causing his chest to become broader and his shoulders to square themselves. Meanwhile, fur continued to grow, with his peach spot gaining white fur. The same white fur coated his wrists and his quills also gained them at the ends of his quills.

His tail then began to change. It lengthened and gained a bushy lair of fur that became tipped in the same white fur that was on his chest, wrists, and quills. It began to sway just after it finished growing. The front of his shoes then began to to bubble as his feet felt like they were extending. The front then tore apart, revealing paw like feet with black claws emerging at the end of the toes.

As the hedgehog's transformation occurred, a shadowy form of a beast began to emerge from the planet, grabbing onto two pieces of the now broken planet for support. It's head glowed as it gnashed it's teeth.

At the station, the final changes began to occur with Sonic. His muzzle began to painfully grow longer and his mouth grew wider along with it. He then felt a pain in his teeth as they grew longer and became sharp fangs, his canines becoming the longer ones as the moved past his lip. As this was happening, Sonic felt something building up in his chest wanting to get out. Snarling just before he did so, he lurched forward and let out a giant roar. The lightning ruffling his newly grown fur and illuminating his now open eyes.

At the same time, the beast finally awoke and gave out a roar. The inside of it's maw glowing white.

At the station, the rods that emitted the lightning finally shut off. The now colorless chaos emeralds dropped to the ground and the transformed hedgehog collapsed, letting out several deep breaths of exhaustion.

Eggman however was in complete glee as he looked over the now shattered planet. The planet was now separated in seven pieces, with large purple tentacles latching onto the pieces that seemed to prevent them from drifting off into space.

"Success, a brilliant success." He said with delight. "It's just as the gaia manuscripts foretold. Now all I need to do is harness it's power and Eggmanland will finally come to be."

At that last part, he let out an evil laugh of delight. Suddenly, he heard a low and angry growl.

He stopped laughing and looked down. At first he didn't recognize the creature below. It was trying to get up and stumbled, clearly not used to the new feet. It eventually managed stand in a hunched position and turned it's head, revealing one of it's green eyes. It was at this moment Eggman realized that the creature was Sonic.

"You've really..." He said, his voice now deeper and rougher. "Gone and done it this time Eggman."

For a few seconds, all Eggman do was stare in surprise as some questions raced through his mind. How did this happen? Why was his nemesis now a monsterous beast? Could it have been a side effect of the machine?

He then shook his head, it didn't matter now. The hedgehog has served his purpose and he would need to dispose of him.

"Ah, Sonic." he said regaining his composure. "That's a good look for you. Festive." At that last line, Sonic' anger was briefly replaced with surprise.

"So long friend." Eggman said before he pressed a button and a glass dome went over where he was sitting.

A second later, the window behind Sonic opened up and he was flown through it. He managed to grab onto the edge, but because he was weak from the transformation, he was quickly losing his grip. He tried to use his other arm to grab to grab the edge, but at that moment he lost his grip and was flung into space.

He began to fall down to the earth, along with the drained chaos emeralds. As he fell down to the earth, he let out a scream that was heard until he vanished from sight.

Meanwhile, the beast looming over the shattered planet looked up and let out a screech before dissolving, it's essence spreading it's evil around the world.

Authors Note: Well that didn't go exactly as planned. You might have noticed one of the changes to the story. Well next chapter you will see one of the main changes to the story.

Fun Fact: This was the shortest chapter to outline, as I basically wrote "Events of Unleashed's intro" to some degree.

See ya next time.