The celestial sisters and robot glared at each other with intense aura clashing one another. The Area was quiet enough for water drops to be heard from deep inside the cave as they prepare for one another to spark the first action to battle.

Emerl made the first move by using his finger guns.

“Taste this ya, alicunts. Boomstick” Emerl said as he launch rapid-fire of energy to the princesses

'That was a terrible joke.' Harmony scolded Emerl

“Luna get behind me. ” Celestia said as she counters by casting a barrier

The barrier is strong, yet it could not last forever against the continuous assaults this robot is using. Thinking quickly Luna prepared a lightning spell to cease his actions.

“Take this, thou low minded golem!” Luna irritably yelled

'Damn girl you don't need to yell,' -a cloud appeared above him - 'apparently the blue one knows thunder.'

Emerl dodged the thunder cloud and began using a powerful energy beam as the sisters separate to dodge the attack. The next second Emerl appeared in front of Celestia punched her in the face, followed by a stunning uppercut on the jaw, then quickly used a combo of kicks, and for the finish he almost landed a enhance axe kick. Before the axe kick can land Luna intercept.

“Leave my sister alone, metal demon!” Luna shouted as she decked him with her hind-hooves.

'Holy faust, Emerl! You got knock the buck-out by a pretty alicunt.' She mentally mocked while laughing.

'Oh don't you start,' Emerl thought back angrily

The moment Emerl hit the ground Celestia launch a powerful fireball at Emerl.

'Damn I guess they're pissed.' Emerl thought as the flaming sphere comes closer.

'Ya think?' Harmony snarkly respond.

Emerl quickly got up up and kicked the fireball back and then charged at the sisters . The sisters dodged the fireball, yet could not escape when emerl grabbed their horns and began spinning their bodies against the walls, then tossed them outside approximately a good mile away from the cave. He decided to give them a break and stayed a bit to plant a powerful cloak/barrier to prevent any other intruders from entering.

'heh I'm glad I could get them out before they can damage the tree.' Emerl thought

'Oh Emerl you don't need to protect my old body,' as Emerl could feel Harmony blushing 'I could live here and besides this place is nice.'

'You do know it will set a lot of problems if the future bearers can't find your old body. Besides, didn't you told me that cutting your old body will feel like being neut-' suddenly Emerl felt cold.

'If you think about finishing that thought, I will give you a real reason to be scared.' Harmony threatened in a cold voice. Emerl quickly stopped the mental chat and began searching for the celestial sisters.

'Each time I say something nice he fucks it up, well I guess he's going to have extra training time when he unlocks his chaos powers.' she maniacally laugh which unknowingly gives Emerl dread.

The field of Everfree

Meanwhile, Luna and Celestia have recovered some strength from the impact and began to plan.
“Sister how art we going to beat this demon?” Luna said frustrated. “I have inflict so much damage, yet it's like that monster keep asking for more. ”

“Well Lulu we have no choice, but to use our best spell against that creature, ” Celestia said grimly before continuing. “it would leave us vulnerable against anyone else especially Discord once that monster notice. However, if we make it back to the Tree of Harmony we might take Discord down.”

“Sister art thou sure the Tree is worth the chance of Discord discovering and finishing us ,” Luna said worryingly. “if it's true, I can tell thou have lost thy mind.”

“Luna I know thou art afraid of Discord, but recall our ponies art depending on us to cease that monster. If we let a challenge to stop us, then we might as well be deserters who didn't save the kingdom we were entrusted with." Celestia said adamantly.

“Oh thou art right sister!” Luna exclaimed with determine bravado. “ Star Swirl the Bearded, King Bullion, and Princess Platinum would weep, if we give up the hard work we had done to unite everyone.”

“Alright Lulu, so far that creature shaked our usual attacks, so we have to hit that creature harder than ever.”

“How art we going to keep that creature motionless, doubtful that creature will fall to the same trap twice.”

“Lulu how art thou in thy illusions and mind spells? ”

“ I art the princess of the night sister, my mind spells can disconnect the mind from the body however long I wish.” Luna looked down a bit shamelessly. “My illusions aren't equally stable when I art moving.”

“Alright I want thou to use the illusion when the creature try to physically hit thee, then stunned that creature so we can launch my strongest bind spell to make his magic turn against that himself.” Celestia gave a grin “ After that we will use it.” Luna nodded.

Meanwhile with Emerl

“You know being in a forest filled with Earth's type of nature would give me an advantage if it weren't for these random canon fodders.” Emerl shouted.

Emerl accidentally encounter some of the celestial sisters' guards and tries to escape from their pursuit. He decided to channel some energy in his back and slow down to give the guards a sense of safety. Just as the guards were eagerly ready to apprehend the robot. He burst out his jetpack and release a speed of mach 2 which pushed all the guards back as they suffered injuries that they can mend. Emerl shut his jetpack and quickly used his camouflage.
After 10 minutes, Emerl decided to use copying ability for his advantage as he spoke from the bush.

“Guards what art thou doing?” Emerl said in Celestia voice

“Mine princesses wherefore art thou! We art here to assist thee against the golem .” The commander said

“Well we art safe commander. we need thee to evacuate since this golem forced us to use extreme measures.”

“Beg mine pardon, Princess Celestia wouldn't be better for the guards to assist thee even more. We art willing to sacrifice our lives as we art against Discord. ” The guard asked with suspicion

“Do thou doubt our abilities as princesses, knave.” Emerl angrily yelled in Luna's voice

“No princess Luna we shall carry out thy orders .” The commander said fearfully as he remember how assertive the princess of the night can be. One guard once accidently bump into her and had to duel her for compensation. He was unable to feel anything as there was a chance he could never walk again. The guards hastily left to spread the false orders.

'There now I don't need to worry about high casualty when the alicorns go full out,” Emerl thought.

'Oh shit I forgot the time for their exam. Oh well I guess I'll let them use their big guns, hopefully they don't attract that draconequus with massive amount of power.' He ahead off to wilderness.
After a good 5 min of flying, Emerl found the sisters with some of their injuries recovered. Emerl brought his finger guns to shoot the sisters. The sisters evaded to the trees, 'Ha sun princess is trying to use stealth like a ninja,' Emerl thought 'well too bad they do not know much about infrared vision.' He target Celestia with a freeze spell which hit direct marked. It froze Celestia before she could react as Emerl used his telekinesis to move the disabled princess against the trees until Luna came out to charge at Emerl. He responds by intercept the charge by making Celestia crash into her as it broke the ice.

Emerl decides to channel two different aura signature into each hand one blue and the other gold.

'How is that creature channelling the aura's in that precision ?' Celestia thought.

'Maybe that creature is using an illusion spell to keep us off guard.' Luna mentally respond

'No sister that is the same combine spelled we used the first time on that creature.'

'Tia do thou think that creature can mimic our magic and power.'

“Hey you're wondering if this is your technique, then you're not wrong and I am matching it exactly.” Emerl taunted with a smug tone which sparked a annoyance in the moon alicorn’s eyes.

“Ha doubtful copycat as thou know nothing beats the original,” Luna boasted at the imitating creature as she prepared a blast of her own. “Come on, Tia let's blast this faker back to his place.”

'Lulu I want thee to charge for the plan after we teleport hence.' Celestia telepathically said to Luna

'Sister this faker claims to be better than us in our own technique. Don't thou want to prove that creature wrong.'

'Sorry Lulu I can't take the chance with pride we must execute the plan if 't be true we want to truly beat that creature. '

'Fine sister, if we lose I am so blaming thee.'

The sisters slowly got up to sense a pair of familiar energy signatures are coursing through emerl as he brought his hands together and fired a giant beam at them. As planned Celestia teleported them out of the blast, yet was sucker punch by Emerl after they appear. He kicked Luna only to paused as the illusion hits it's mark

'Crap it's a trap,' Emerl mentally swore 'I should have known the night princess will find a way disconnect my mind from my body.'

'That's what you get for getting arrogant against multiple opponents,' Harmony commented 'you could have ended this and just pass them for having values of Harmony.'

'Harmony it's warrior's pride to fight, besides I need to focus on getting rid of this spell.'

Celestia used this chance to bind his body from moving by forcing the magic inside to turn against himself. The sisters began charging at the robot as they used both hind hooves to strike at Emerl in the face upwards. Then, the sisters each used several charged magic blasts to keep him up there.

“Shall we end this sister for Equestria!” Luna yelled in determination.

As Emerl's body reached approximate 4 stories the sisters teleported above him and prepared a finishing spell as they expanded their wings. Luna summoned 50 pure energy- shaped stars and fired all in great fury as Emerl's body launch downward at a fast pace as the assaults end Celestia created an enormous sphere of energy that can guarantee to eliminate a foe and toss it down at the robot.

Meanwhile at Discord's place

We find our draconequus flipping through pony vision right now he is view western.(Think of the ponies changing each time he snaps his talons)

“Oh my even with the amount of chaos I brew it gets so dull when people aren't making an effort to challenge moi in a spark of change.” Discord complained

Discord snapped his talons and the confuse ponies are in a mobster style. “It seems you didn't pay for my generosity so time to sleep with fishes ya dumbshit.” The leader pony said. The mobster was about to ice this fool until Discord snapped his talons to end the show. The confuse ponies were back to normal and they ran off scared for their lives.

Discord began walking outside “I know I have those sisters to face, but I want something different. Something more, ” he paused as he notice a giant fireball at a far distance. “ it seems little Celly has been hiding bit of power,” he examine the ball of energy. “ Celly is bit of a mother of hen to be using that at little rock so something must happened to cause a temper on the little sunny princess.”

He grinned as he took out some sunglasses, popcorn, cotton candy cloud, and watch the fight to see who is forcing the sisters in such a condition.

Back to the fight

After the enormous micro-sun sphere hits the ground it created a massive explosion that burned about ½ miles of trees and wiped a good portion of the land off, yet it seemed to have eradicated that robot.

“We did it sister we beat that annoying demon. ” Luna said tiredly

“Luna if that creature survives this I don't think we can last a minute.” Celestia responds with match fatigue

“Sister thy attack could have killed discord if given the opportunity. I doubt a being such as this can last what a chaos god could not.” Luna reassured until a familiar voice yelled right above them.

“Sorry dear Lulu, this demon is more stubborn than you thought as he somehow dodge the flaming ball of death.” Emerl said in Celestia's voice mockingly.

At the sky, Emerl seemed clearly alright with most of the damage recovered and his eyes seemed to dim as if either silent irritation or exhausted from the fight. Before the sisters had a chance to respond, Emerl quickly dived directly at the celestial sisters with both open palms and channel energy to them. He push them and their bodies began to fall from a gravitational force that caused the sisters to drop on the ground.

“How art thou doing all this?” Celestia said fearfully

“I could explain everything little spark, but we have an eavesdropper. I can't afford to show you more of my abilities.” Emerl said in his normal voice

The big shock that Emerl survived left the sisters in disbelief since their chance to win was diminish as they are extremely low on magic. The next few seconds the robot's left hand began to glow as his right kept the sister in a telepathic hold he jabbed his left hand into each of the sisters' pressure points in their body disabling their abilities to channel magic or movement.

“You mares put up a better fight than expect, but I have ways of changing the types of energy in me. The most effective way to stopping me was Luna. If only it lasted longer then mini-sun bomb would have done some massive damage.” Emerl said

Then, he channel both index fingers in each exact aura color blue and gold to flick it onto the sisters forehead and sending them to subconscious. He stared at the particular direction where Discord was at.

“Oi Chimera inbred if you're seeing this then here's a present,”- Emerl flips the bird- “ I'm the guy that will make sure Harmony lives.”

Meanwhile with Discord

“Mmm that is quite the metal monkey,” Discord snapped his talons, yet nothing is happening. “he is more than meets the eye.”

He smile greatly as he plans a great challenge for the mystery robot.

Author's Notes:

Sorry it took so long, but I had to think hard on the fight and discord's regular behaviour in order to get a good feel. Other than revising and editing the draft, I had to double check if it made sense or that it wasn't off. Give me a comment if I played ranging from terrible, bad, ok, good, or great on the characters, writing, and whatever you think that improve this story. (As this is a sonic crossover E, D, C, B, or A)
Like to take note: Emerl went easy on them since he could have done the pressure points in the beginning. Plus, he had learn alot from Harmony so he may have some abilities to control time and space as he used for chaos control except with Harmony's energy. I also thought since Harmony's energy can be used other than magic such as ki, Reiryoku(spirit energy), chakra, and etc. Either way Emerl does know how to convert a form of energy to another.
I may need to make a list or at least the daily training before release of this emerl before starting chapter 3 since I will feel like I will be pulling random excuses for Emerl in avoiding certain situations. The displace token I would make it after Emerl gains his chaos energy which is near the end unless someone can explain why and how I should do it sooner.
Metal monkey comment is sorta saying metalic 'monkey see monkey do' phase
Extra note: I am thinking of providing songs to the stories should I. Yes, No, or it doesn't make a difference. I know it mainly depends on quality than quantity, but I thought why not just for the heck of it.