Author's Note

Sorry this chapter's kinda late, guys. I had other things to attain to, which kept me from writing.

Anyway, the story's really putting pressure on our heroes now, isn't it?

If you want to see how Wily recruited the villains, (and I'm fairly sure you do,) I'll post that in a bonus chapter, so keep an eye out for that.

Skull Castle Assault: Sewers

The next area in the Skull Castle was the sewers. The whole area was coated in a yellow-green mist, and it smelt terrible. There was also a bit of radioactivity in the air, which read on Diamond's radioactivity scale as a 30, which wasn't that serious.

"Bit of radioactivity down here, Diamond. Think you and the ponies can take it?" Mega asked.

"The ponies, they'll be fine." Diamond said. "Me, well, it's kinda obvious. I practically LIVE in Liphidite crystals, which is a 500,000 reading on the scale. This area is no higher than double digits, so I'm gonna be good for a while." he added. The heroes decided to press forward anyway, even though the area was irradiated and Diamond didn't have his Mega Armour. They hadn't gone far when a loudspeaker appeared from one of the pipes.

"Nyahahahahahaha!" Wily laughed from the speaker. "You've done well to make it here. I've got the last Element of Harmony locked in my room. But if you want it, you gotta get it!"

"That...doesn't explain all this sewage, Wily." Proto Man said.

"Right, the sewage. Poisoning these ponies is one of the goals I have in this world. That way, it'll be a lot easier to turn them into robot slaves." Wily said. "But...if you want me to cut the sewage off, defeat my Kamegoro Maker. You'll get another Element from it as well. Have fun! Nyahahahahaha!" The loudspeaker disappeared back into the pipe it came from as Wily finished.

"Not good. How's everyone doing back there?" Mega asked.

"I've only recieved one dose of radiation. My visor tells me that everypony else has recieved quite a lot." Diamond answered. "I have the answer, though. I called a Supply Drop while I was waiting for you guys at the shield and it contained quite a lot of Rad-Aways. Everypony, cleanse yourselves in these to wash off that radioactive dust."

"I don't see how it'll help, but okay." Applejack replied, but she and the others proceeded to coat themselves in one Rad-Away each. When they were done, Diamond gave the thumbs up to let them know the radiation was clear and they pressed on.

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The team passed through the highly toxic sewers with little interference. A few Big Fish, Mets and an Armour Joe were the only enemies down here, making the walk to the boss door uneventful at best.

"Upgrade done yet, Diamond?" Mega asked.

"Not quite yet. It's on 89%." Diamond answered. "Think Wily's actually gonna turn the pipes off if we defeat this boss?"

"If I know Wily, then probably not." Proto Man said. "Let's just beat that Kamegoro Maker and grab the next Element." he added. The team entered the door into the clean water of the next room, with a machine above the pool. This boss room, like the last one, had no ceiling, but an even floor. Most of the room was filled with clean, blue water and the smell and radioactivity was non-existent.

"There's the Kamegoro Maker. How do we break it?" Diamond asked.

"Destroy the Kamegoroes it makes." Mega answered. "Let's see how well your Photon Rifle does." he continued as Diamond dug out his gun.

"Engage Shadow Blade!" Proto Man shouted into his system, his armour changing colour as he did. He then threw a couple Shadow Blades at the incoming Kamegoroes, destroying them near instantly. Diamond emptied his current mag on the next few Kamegoroes, leaving them mere scrap metal. Mega Man changed to Metal Blade and tossed a couple at the next few, but Metal Blade had no effect on these guys, so Diamond took over with his rifle. Twilight and Starlight finished the job with thier combined magic beam aimed directly at the Kamegoro Maker and disintegrated it, leaving it beyond Wily's repair and leaving only the Element of Honesty behind.

-Upgrade complete! You can now Meganize into a new armour!

"New armour. Let's grab the Element first, though." Diamond said, moving forward to grab the crystal apple. Before he could grab it, however, the chestpiece of his robotic body opened and the Element flew into it's slot in the storage system.

-Element of Harmony Acquired!
-This is the Element of Honesty, the fourth of six. Locating the remaining Elements is highly recommended.
-Applying this to your Harmony Buster will shoot pellets that will increase in power if someone close to you tells a lie.

Diamond dismissed the notifications before he said "MEGANIZE ME!!"

[Transformation Scene]

Diamond jumped into the air and was coated in a flash of light. As it faded, his green jumpsuit disappeared to be replaced by light blue bio armour.

Next, Diamond's armour expanded into lapis-coloured boots, shortly followed by his chest being coated in light and forming his blue breastplate, followed by the backplate.

Then, the hands were coated in light to form Diamond's gauntlets. One of them would be able to transform into Diamond's Harmony Buster later.

Lastly, the Mega helmet formed on Diamond's head, with it's appearance changing his eyes from hazel to a robotic blue. This ended the process.

[Transformation End]

No sooner had Diamond touched the ground, Diamond's armour glowed again, shortly having it's material replaced from metal to crystals. His Zero Suit Grapple Beam was fastened to his helmet in the form of a horn. Rapid notifications appeared on his visor shortly later.

-Crystal Armour Acquired!
-This new armour will draw magic from the area around you and use it to power your Grapple Beam, now renamed the Magic Beam.
-Crystals direct from the Frozen North increase the defensive properties without hindering your agility, especially considering those crystals are really heavy usually.
-The Elements can expel more power than before without putting strain on your systems, and your Zero gadgets can now be used in armour.

-Rainprism Acquired!
-The Rainprism is a passive weapon, engaged when you use the Light Dash mobility weapon.
-Colliding with something while using this attack negates all contact damage and releases a shockwave similar in power to the Sonic Rainboom, thanks to the Element of Loyalty.

-Gem Shield Acquired!
-The Gem Shield is a defensive sidearm useable with your secondary Buster.
-The shield is formed by magic, is virtually indestructible and can even ward off magic attacks, fueled mainly by the Element of Generosity.

-Nature's Regeneration Acquired!
-Nature's Regeneration harnesses the natural energy in the magic absorbed by your armour to restore your Power over time.
-Animals in the nearby area will be attracted by a single whistle to enhance the Power regeneration rate when the ability is used, courtesy of the Element of Kindness and Fluttershy's ability to communicate with animals.

-Apple Kick Acquired!
-This weapon is similar to Charge Kick, only a lot stronger.
-It is used in the same way as the Charge Kick - slide into stuff to attack it.
-Sliding into enemies will drop explosive crystal apples in the immediate contact area, powered by the hidden power of the Element of Honesty.

"I...I never knew my Element had that potential!" Applejack said.

"Neither did I, Applejack. But if Diamond was able to unlock it, perhaps he should keep them on him." Twilight suggested. She turned back to him, only to see energy being released from his armour in huge spurts. Diamond's visor read:

-WARNING! Power Overload! Remove an Element of Harmony immediately!-

The Mane 6 wasted NO time. Mega opened Diamond's chestpiece and the two unicorns and Twilight used their magic to yank the Element of Loyalty from it's socket. The energy spitting out of Diamond's armour ceased as he collapsed to the floor in immense pain.

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Meanwhile, down in the Skull Castle Dungeon, the ponies imprisoned were starting to get restless. Wily had a few robots stationed there, and they weren't letting anypony escape anytime soon. Celestia and Luna, however, had remained calm, even though Crash Man and Commando Man were guarding their cell.

"Prisoner Report!" Bass cried out as he teleported in. Commando Man rushed forward as he materialized and saluted.

"All accounted for, nothing to report." Commando Man said quickly. He was obviously scared of Bass, but didn't want to show it.

"And as for you, Luna, KK, you're coming with me for now." Bass said. "Let them out, Crash Man!" he commanded. Crash Man swiftly obeyed and cracked the Weapon Lock with his Crash Bomb, letting the princesses go.

"What do you want with US?" Luna asked. "Not like we can do anything anyway. You had Discord remove our horns!"

"Don't forget about our wings, Luna." Celestia said. "But anyway, why would you release us anyway? We're the enemy."

"But you don't HAVE to be." Bass said. "We formed an alliance with a few guys you've fought before, and...why am I talking? It would be better if I just showed you." he continued before warping out, taking the two sisters with him.

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Wily, Queen Chrysalis and King Sombra (somehow) were more than expecting the arrival in Skull Castle Peak. The rest of the villains (also somehow) were not, but Bass filled them in as Wily confronted the two sisters.

"What do you want, human scum?!" Celestia snapped, initiating a fight stance. Luna quickly imitated as best she could.

"Calm down, you two. I just want to talk right now." Wily stated. "But if you wish, I can always blow the castle and everyone inside it to pieces." he threatened cleverly.

"Fine. We're listening, but I don't think we'll be interested in anything you have to say." Luna grumbled.

ONE WILY MONOLOGUE LATER...

"...and that is essentially the deal. To put it simply, you join me and we'll unlock the evil side of your person...or...pony...whatever. In return, we make the prisoners our slaves and take over the rest of the planet." Wily finished. "You refuse, and the least you get is your powers back and we blow this place up. What'll it be?"

Celestia considered this for a moment, then agreed, even though Luna tried to warn her that she was making a ginormous mistake. "We gave you what you want. Now let everypony go." she said.

"Who said I'd do THAT?" Wily asked them sarcastically, his hand hovering over the detonator. "Set the timer, Sombra!"

"But...you said-" Luna began before being cut off.

"Remember when I said I'd disarm the explosives? You should have known that I never stay true to my word." Wily gloated. The heroes did beat my Kamegoro Maker, so I'll keep that promise, though," he added, hitting a button that said "Cease Sewage".

"Timer's set, Wily. Now let's hit these two with a bit of darkness..." Sombra said, charging his magic. When he released, both of the princesses present were engulfed in visions of thier worst fears, which would later evolve into something dark.

ONE SLIGHTLY-LONGER-THAN-ANTICIPATED PROCESS LATER...

The two sisters had become evil versions of themselves. Celestia had become the Empress of the Sun, Daybreaker, while Luna had become the Queen of the Night, Nightmare Moon. Discord (who had been tricked again, this time by Wily,) snapped his fingers after they'd finished maniacally laughing to restore their wings and horns.

"Alright. The Legion of Doom is now reborn and ready to go. We'll detonate this joint and take over the rest of this planet, and there's NOTHING that can stop us!" Wily said, almost certain that his plan would work out.

"And...what do we do after Equestria is ours?" Discord asked quickly. "There's got to be something beyond our planetary borders."

"Oh, but there is, o great Lord of Chaos." Wily answered. "After we take over Planet Equis, one of us will stay and watch over while the rest of us travel to the next planet on my list."

"But...who's going to stay behind, Wily?" Cozy Glow asked. "And why only one of us? Surely having more than one would give us a better chance to keep control."

"You make a good point, little one." Wily said. "And who better to stay behind than literal royalty? I have a feeling Daybreaker and Nightmare Moon would do the best job ruling over the planet when we're done."

"Excellent. And like you say, Wily, there is NOTHING that will stop us this time." Nightmare Moon said. "I know we villains say that every time, but this time, really, NOTHING will stop us!" she finished. The Legion of Doom began laughing maniacally at this statement, as they knew they'd be doing better than their previous attempts. Wily proceeded to hit a big red button that said "Detonate" to start the timer on the explosives in the castle, which would go off in three hours.

====================================================================================================

Diamond had just come to his senses when the room they were in began flashing red. He immediately got to his feet, ready to fire before a monitor appeared from the ceiling. The water drained from the room to make more space for it, and the Legion of Doom appeared on the screen.

"NYAHAHAHAHAHA!!" the Legion laughed.

"You've done AWFULLY well, all of you. Really, you have! But your time's running out rather fast." Wily said. "If you're going to storm this castle, you'd better be quick doing it!"

"What did you do?!" Mega Man yelled into the monitor. "I swear, when we get up there, you're going to be seeing STARS!" he threatened, charging his Buster quickly, but Twilight used her magic to restrain him.

"All I did was activate a self-destruct sequence, set to go off in three hours. I've been generous and given you time to reach me. But you'd need all six Elements of Harmony to stop me, and HOW many can you carry at a time?" Wily smirked as he said this. "A pathetic three is the answer to that one."

"We've got every villain in Equestria here, boys." Chrysalis said from the background. "From Nightmare Moon to Cozy Glow, and EVERY CREATURE in between. Even Discord's here with us."

"Did...you...just...say..." Fluttershy said, triggered by hearing Discord had gone bad again.

"Now, Fluttershy. I'm sure this is all a big misunderstanding-" Diamond began.

"DISCORD!!! WE MADE SURE YOU'D BE REFORMED, HOW COULD YOU DO THIS TO US?!" Fluttershy shouted, taking no notice of Diamond at all. "LET ME TALK TO HIM NOW, OR YOU'LL BE SEEING A SIDE YOU DON'T WANNA SEE." she threatened.

"I never knew you had that side to you. Alright, Discord. She's all yours." Wily said, with Discord materialising in front of the screen a half-second later. "But you guys are wasting time by doing this."

"Dang, he's right! Come on, team!" Diamond said, blasting the monitor apart. Fluttershy immediately cooled off and the heroes sprinted (or, in the case of the ponies, galloped/flew) onward.