Birkin in Equestria

*Beep...Beep...Beep*

William's vision slowly came back to him as the sound of a heart rate monitor filled his ears.

"Everyone, he's waking up!" the familiar voice of Pinkie Pie said.

William looked around to see the Mane 6 and Princess Celestia standing around his hospital bed. He sat up in his bed with a grunt and looked around. And for the first time since he got there, his cutie mark was clear to see (a red and white umbrella seen from above).

"What happened? I remember bleeding out in the hallway, but everything else is blurred." he said as Celestia got an uncertain look.

"Well you in a way...….murdered a threat against Equestria." Celestia said as she got a look of disgust at recalling the events.

Everyone in the room looked at Celestia in utter shock.

"He. Killed. Tirek?! HOW?!" Twilight exclaimed in shock and Fluttershy fainted.

"With one strike of his hoof. If I could even call it that..." Celestia said.

"What do ya mean Princess?" Applejack asked.

"His right front hoof was mutated beyond recognition. It was covered in some sort of muscle tissue, claws where sticking out of the end and a big eye was looking out of his shoulder. He ripped out a third of Tirek's insides with it. I really don't want to go into further detail." Celestia explained.

William was rendered speechless for a few minutes before he managed to get his ability to speak back.

"What happened after I committed the crime?" William asked.

"You screamed for help, your hoof returned to normal and you fell unconscious, to put it mildly." Celestia explained. "Although you also mumbled something while you were unconscious." she added.

"Did you understand anything?" William questioned curiously, recalling that he had done the same thing when he fell asleep on the way to Canterlot.

"I heard you say 'G is my creation', but the rest sounded more like gibberish." Celestia answered.

William searched his memory, but again found nothing. It was now beginning to get frustrating for him.

"Argh...Why does it sound so familiar?! Why can't I remember?!" William said while frowning.

"There might be a way." Celestia said, which got everyone's attention. "I know a spell that can look into somepony's memories. It will also make everypony present able to see certain points as well. Although is this okay for you William Birkin?"

William thought for a few minutes before giving his answer.

"If you promise to only show things that has to do with what happened yesterday." William answered.

"Sorry, but I can't control that." Celestia said as she lit up her horn and lowered it towards William's forehead.

"Wait what-" William said as Celestia horn made contact with his head and he became paralyzed.

William's eyes turned a glowing white as all his memories came crashing down on his head. His childhood, his schooldays, college, the Umbrella Corporation, Albert Wesker, Annette, Sherry, the G-Virus and his death.
A cloud of smoke was emitted from his horn and formed a form of screen that played a selected memory. The first memory they saw was from Birkin's childhood and showed how he was bullied by his classmates because of his knowledge within science. Although Celestia and the Mane 6 were confused by the change in species, they continued to watch silently as a new memory came up.
This one was about assassination.

The group's ears were violently invaded by loud bangs that went on for a few seconds before William and a man wearing sunglasses entered the room to see a man lying on the floor with multiple holes in his chest and he was bleeding heavily.

"A-are they gonna help him?" Fluttershy asked as she was on the verge of throwing up because of the amount of blood.

Albert leaned over the man and to everyone's surprise, taunted him.

"Time to die, doctor." he said as William leaned over the dying man as well.

"I will take over your research." William said before he laughed menacingly.

Everyone's jaw dropped at that statement.

"That doesn't sound like something William would say at all.

They continued to watch different memories come and go as they saw him being with his daughter, doing research with his wife and producing bioweapons. Eventually one memory that William recognized as the dream he had two days ago.

William was cornered by a group of men wearing black clothing and gas masks while holding guns pointed at him.

"Doctor Birkin, you'll come along with us quietly." one of them said in a demanding tone.

"You think I didn't know you were coming? This is MY life's work! I'm not handing over ANYthing!" William answered while grabbing something inside his coat.

"We have our orders, doctor Birkin. I'll ask you one more time..." HUNK said.

William pulled out a gun, but just as he did one of the soldiers opened fire and William fell onto the ground while bleeding heavily. Sounds were muffled as William saw them take the case with T and G-virus samples away from him. He sat up and took out a syringe that had a G-Virus sample inside it.

"*cough* You don't get away that easily." he said before injecting the sample into himself.

Mere moments after this his wife came into the room and saw the empty syringe.

"Dear God William. What have you done?" she said worriedly as William got on his feet.

"G is my creation!!!" he shouted at the top of his lungs like he hadn't even heard Annette and began walking after the soldiers that had taken the samples.

The group were left speechless as they witnessed William mutate and slaughter HUNK's team. Fluttershy passed out again when she saw the few people William encountered turned into zombies. Although they got to witness William still retaining some humanity when his daughter was being attacked by a police chief. Even if what he did to the chief didn't seem good.
Soon the memory stopped and one last memory began to show. They saw a girl grabbing a metal rod that she used to stab William right in the eye.

"You like that?! Goodbye fucker!" she shouted before pulling the rod out making a lot of yellow liquid pour out of the eye as the blob that once was William screeched in pain.

The train carriage he was on was disconnected from the train and he was caught in the explosion, then everything went black.

The "memory cloud" disappeared and William eyes returned to normal, although his expression changed to one of utter shock and horror.

"W-William?" Twilight said as she took a careful step forward.

William looked at his hooves in disbelief of what he now remembered about his past. He squeezed his eyes shut before he ripped off the cables that were connected to the monitors next to the bed, jumped off his bed and ran out of the room.

"William!" Twilight shouted as she and the rest of the Mane 6 followed after him.