Who are the Vacuum

(If you know where I got the Name of the OC here, please tell me. It's been bugging me since CapitanAwsome999 told me it sounded familiar to him.)

Rainbow Dash

Rainbow was talking to Applejack about getting Sonic a job, and letting him stay for half the profit he'd make. Applejack said she'd agree to it if Sonic was willing. She went to Sonic and told him about the arrangement that she made with Applejack. Sonic said it would work for him and took the job. Later, Sonic and Dash were talking at Fluttershy's which still had the big hole in it after Sonic's run-in with it. Dash was as happy as she could get, and then Pinkie Pie came around.

"Dashy! Sonic! Are you alright!?" she asked.

"Fine, why wouldn't we be?" Sonic asked.

"There was a fire at Sweet Apple Acres!"

"What!?" Dash exclaimed. "Is Applejack alright?"

"Everypony's fine, but there was a note," Pinkie pulled out a piece of paper and handed it to Sonic. Sonic read what it said and raced off for the Aces with an unidentifiable look on his face. It looked like fear, worry, and determination all in one.

Dash felt something pull at her heart that made her follow him. But not before Pinkie had a meltdown and jumped all over the place.

"What was that?"

"Last time my Pinkie sense said something that big, Twilight started believing it," Pinkie said. "Even then it wasn't that drastic…" That made the decision for Rainbow. She flew to the Acres and looked for Sonic.

Sonic Impact

Sonic was investigating the area of the fire. Thank God it didn't go very far before it hit water. And after that the Fire Department Ponies were able to put it out quickly. There was no evidence that this was an accident, the wires that powered the lights for Ponyville all ran underground. There was nothing leading anyone to believe that it was started by a campfire, and at the time there weren't any clouds over Sweet Apple Acres, so it couldn't have been a Pegasus mistakenly causing a lightning strike.

"Sonic!" He heard Dash yell.

"What's up?" he asked.

"Pinkie had a huge Prediction. Last time it was anywhere near that big, Twilight started believing in the Pinkie sense."

"Well, it hasn't happened yet. Everything's fine." Then Sonic felt it. A spine freezing sensation that could only be described if you stood at the South Pole without anything covering you, not even fur. It made Sonic double over in fear.

"Sonic? What's wrong?" Applejack came running. As did the other Spirits of Harmony.

"GET AWAY!" Sonic yelled.

"What's gotten into you?" Rainbow asked.

"He's here!"

"Who's-" Then it hit Dash harder than a shovel. "You don't mean-!?"

"Exactly!"

"Girls, we have to get out of here!" Dash said. But it was too late. Out of the shadows a blinking blue sword swung down, landing where Sonic was a second before. Then the figure holding the Sword came out of hiding, like a chameleon showing itself, from its hiding spot.

"You're good, Sonic the hedgehog," The man said. "Or should I say 'Sonic Impact' now?"

Sonic's mind swelled with rage. Now that he knew what really happened to his family, the very sight of this guy made sonic want to take up firearms class for rocket launchers.

"Necromius!"

Rainbow Dash

Rainbow was there when Sonic last met Necromius. Somehow Necromius was thinking that he was supposed to kill her when Sonic was still alive. The minute Sonic saved her was the minute Necromius set his sights on killing Sonic. She had to wonder why she didn't feel his presence now, when she did the first time.

"You remember me this time," Necromius said. "I'm so flattered."

"Shut up," Sonic said. "You caused this fire, didn't you?"

"Yes… and my act of arson did its job wonderfully. You showed up."

"Why do you want to kill me?" Sonic asked. Come to think of it why DID Necromius want to kill Sonic?

"The Vacuum is a group of special creatures who want nothing short of perfection. Anyone in their way will be eliminated, that is my job. I am in charge of hunting down the fastest creatures alive and killing them until there is nothing to stand in the way of the Vacuum. And you are currently the fastest thing there is. No one yet has-"

"Blah, Blah, Your evil plans, Blah!" A red Pegasus rushed up and head butted Necromius so hard something might've snapped. The Pegasus turned his attention to Sonic. "And you! You couldn't do this to him because?"

"Right now, I'm the only one he can kill," Sonic responded.

"Sorry, I missed that part," the Pegasus said.

"Jeez, Knuckles," Sonic said. "You couldn't wait two seconds, could you?"

"Knuckles!?" Applejack shouted. "The Red Echidna that guards the Master Chaos Emerald on Angel Island!? That Knuckles?"

"My name is Iron Knuckles now, and I came to see him."