Picking from last time, Sunset was at her place, following her encounter with Emerald Elf.
"I need to find out who's the elf, before he causes more trouble, but that guy is hard to find and who knows where he will strike," Sunset said as she put on her costume. "But maybe a late night patrol can clear my head."
Meanwhile at Mercer Corp…
"But… but what about the Solar Eclipse?" Sassy asked Darell. "She's battled both Sandstorm and Iron Bull. She can trace them back to Mercer Corp. To me!"
"Enough! You whine more than my son. I can't have weak people in my organization, Sassy. Do you understand?"
"I understand, Mr. Mercer. I'll do what I'm told."
"That's all I ask. Now run your experiments like a good little doctor," Darell said as he left Sassy alone in her lab.
Sassy went to work on her power armor tech and put it on unaware that Emerald Elf broke in and locked her inside and started the generator.
"Who's in there? Who turned on the key?"
She struggled to get out as the generator was fully charged and zapped her with her armor.
Miles from there, Solar drops on a building to see a bright light.
"Whoa! That's Mecer Corp. Travis's dad could be in trouble," Solar feared.
Solar quickly flew over there just as the containment team were trying to fix.
"What happened?" Darell asked.
"It's Dr. Saddles. She's down, but the doors are shut.."
"Out of my way," Darell unlocked the generator room and went inside. "Sassy. Doctor?"
He sees Sassy lying on the ground on top of some rubble.
"Sassy."
"I got it," Solar came in and lifted the rubble off of her with her magic then Darell drag her out.
"Is she?"
"She has a pulse, sir. But it seemed her harness had fused to her skin."
"I'm not weak. I'm not weak."
"Sassy, please get up."
Her hair grew longer and the hair tentacle grabbed Darrell and put him through a wall.
"Silence, you imperious moron!"
"Whoa there, slinky, Mr. Mercer just saved your life as did I!"
"You!" Another hair tentacle grabbed her. "Don't not insult my intellect, hero. You tracked me down and tried to destroy me, as I knew you would."
"Destroy you? But I don't even know you."
"Oh, but I survived. More to the point, I've improved. You have failed and your failure has given me a new life! Sassy Saddles was weak. I'm Madame Mayhem!"
"Look, Double M. Have you thought this through? The next Solar Eclipse who finds you under a pile of debris might view this as a cautionary tale."
"Glib, does not equal clever, Solar!"
Sassy slammed Solar across the room.
"Yeah, but the ratio of living hair to sanity has not been established either."
"Do you ever shut up?!" Sassy tossed her to the ground.
"No, my fans expect to crack a side joke every now and then."
Sassy chased after her around the lab.
"You're slowing down, but this armor never tires and soon it will crush…" The core of her suit started to beep."
"An alarm clock too, mam it comes with the perks," Solar exclaimed.
"My apologies, Solar, but I have places to go, and worlds to conquer. So your doom will come another day."
Sassy headed out of Mercer Corp in a hurry.
"Why do I have the feeling that the Elf had something to do with it?"
Much later…
"I cannot believe I once lived in this anemic hovel," Madame Mayhem was her house. "Well no more! No more I'm sorry Mr. Mercer. Yes, Mr. Mercer. Please, Mr. Mercer. How I grovel before that man. But soon the whole world will grovel before the genius of Madame Mayhem. But first I would need a power source that gives out mid-battle. But this will do for the short term," Sassy replaced her core with a new one. "But I need a more permanent solution to guarantee the Solar's destruction.'
The next day at the Equestria Fair…
"I'm telling you Sunset, there's something wrong with Travis."
"Twi, the football has gone to his head but look at him he's a walking commercial of happiness."
"Is not that, he's been acting weird, weirder than Pinkie of all people," Sunset replied as the two cross paths with Daniel and Adagio Dazzle.
"Well, this is awkward," Adagio said.
"What's that?" Dan looked.
Sunset looked up to see Madame Mayhem scaling building to building to the Delta Design Building.
"Ooh, bad stomach, ate too much cotton candy," Sunset faked it. "Gotta to use the bathroom."
Sunset headed off just as Madame Mayhem broke in.
"Ah, the old stomping grounds," Madame Mayhem exclaimed.
"Sassy? Is that you?"
"Dr. Wenton, how nice of you to see you again," The villainess greeted him by holding him in the air. "Now perhaps you will recall that when I was last employed here, I was working on a long-term power source."
"The Valet Core. But…"
"My work! And I once departed you possession of it. Now in hindsight, does that seem fair?"
"It's R&D, Vault 12!"
"My lucky number."
Madame Mayhem dropped him and headed to the R&D room and saw it.
"Ah, like an old friend," Madame Mayhem prepared to grab it.
"Gangway! Coming through!" Solar jumped over and grabbed the core from her.
"Solar!"
"Hey, Mayhem. Love the new suit," Solar commented, seeing Madame Mayhem in a tight purple suit.
"Hand over the device."
"I'm thinking, no!"
"Then you invite your doom. You are in enclosed space, sun-head. Where can you hide?" Then Madame's hair became sawblades.
She dodged the sawblades then fired a magic blast at her that blinded her allowing her to leap over her.
"You will suffer this indignity, Solar!" She screamed as she went after her.
…
"Hello there," Solar greeted . "Being chased by a mutant hair lady. Want this. What is it?"
"The Valet Core. A power source that holds massive charge for years."
"Thanks. You should hide now."
Solar left the building with Madame Mayhem right behind her.
"So, miss craze hair needs power. That explains why the alarm clock and why she took off so fast. So all I have to do is play keep away until her tank is empty. No sweat."
Madame Mayhem whacked Solar from behind with a hair tentacle and sent her crashing into a ferris wheel carriage then down to the ground.
"Okay, maybe a little sweat," Solar said as she got back up. "And now, back to our regularly scheduled chaos.
Solar did a backflip and saved both Twilight and Rarity from Mayhem's pursuit.
"Thanks, for the company. Love to stay, but I've got a doctor appointment," Solar said as Madame Mayhem slams her.
"You have horrible bedside manners," Solar blasted a magic blast at her but Madame dodged it.
"Hand over the deceive you miserable excuse for a sun!"
Then a caramel apple landed on her head.
"Oh, you sweet talker you."
Solar hurled multiple caramel apples to her which all of them made contact with, then Solar grabbed her by the legs and slammed her to the ground. Madame Mayhem got up and used her hair to grab the closest object she could find and chucked at her but Solar shot it down with a fireball.
"Don't worry, Solar, I got your back," Rainbow prepared to attack her.
"No!"
Just as Madame Mayhem was about to react but Solar pushed Rainbow away.
"Appreciate the help, fangirl, but keep it clear. You're not pretty enough to save twice."
"Right. Smack her one for me," Rainbow agreed.
Madame Mayhem blindsided her then grabbed Fluttershy.
"Fluttershy!" Pinkie cried.
"I should've seen it sooner, Solar. You're weak. You can't bear to see anyone hurt."
"I can learn to make an exception."
"And the thought process is so transparent. Stall until her power runs out. This core has at least an hour of juice. And think of the damage I can do in that hour, starting with the girl."
Madame Mayhem dropped Fluttershy on top of the Roller Fever Ride.
"Choose! The device or the girl!"
No one and I mean no one puts one of my friends in harm's way.
"You want it so bad, then fetch!" She tossed it to the other side of the fair.
Madame Mayhem went after it, just as Fluttershy struggled to maintain her grip but Solar grabbed right before she lost her grip.
"Gotcha," Solar as they landed on the ground.
…
"Finally, it's mine!"
"But you get the chance to use it. Not as long as I'm conscious."
"A situation easily remedied."
A hair tentacle grabbed her leg and Solar slammed on the ground.
"As I was saying…"
Solar shines her Solar Signal at her bliniding her then Solar grabbed the cores with her magic then kicks her at the chest knocking her out.
Much later, the police arrived as Sunset arrived.
"Sunset, what the apple tree happened to you?" Applejack asked.
"I headed out of the bathroom then saw a freaked out villain coming to the entrance so I hid until it was over. What happened?"
"Solar kick her butt like this and that then saved Fluttershy," Rainbow explained.
"Uh, what happened to Travis?" Rarity asked. "He was with us when that brute attacked."
At the Mercer Penthouse.
"I'm talking about The Emerald Elf," Tiger Claw and Darrell were talking. "The nut job attacking Mr.X operations. And far we can tell, he's using a lot of Mercer Corp tech.
"My tech has been stolen. I lost my top scientist, my lab was destroyed and my projects are at risk. Why would I be behind all that?" Darrell asked him.
"Okay, you have a point, but the Elf…"
"Is a common enemy meaning our common goal is we have to unmask him before it is too late," Darrell replied.
The next time is the conclusion of the Emerald Elf Saga