"-and be sure to record the pattern of flickering of Candis four, five and seven, not just how bright they are tonight, Spike," Twilight called back to the baby dragon as she looked through the telescope on her castle balcony.
"Right, right," he mumbled as he looked at the glowing nodes of the machine, flipping on three of the switches next to them.
Finally prying her eye from the telescope with an energized, but mildly wanting face, Twilight returned inside. "how are our test subjects doing tonight, Spike?"
"Subject," he corrected as he reached for his comic book again.
"What?"
"We only have one test subject tonight, Twilight. Two used their one night skip tolerance tonight and the other three said that the pay wasn't worth the sleep they were losing, so they quit."
Twilight just stood there for a moment, with a slow twitch to her eye.
"Ugh!! And tonight is the clearest night we've had in weeks!" She growled loudly as she went straight to the sofa.
With a quick look at her meager one pony worth of data flowing in from the controlled room upstairs, she flopped on the couch. "How am I supposed to test how star behavior effects the flow of Æther around Equis if I don't have a wide spread sample to minimize error with the law of averages on the nights I can actually record the stars!?" She ranted, gradually growing into a yell. "I'd be up there hooked up to the machines myself if I could, but becoming an alicorn changed the composition of my magic and my data can't be pooled with the data of other ponies anymore!"
She finally flopped over and firmly planted her face into a pillow. "Uuuugh!"
"Couldn't you just, I don't know pay them more? As a princess you do have a decent sized coffer, you know."
She lifted her head off the pillow and looked at her assistant with worry and empathy. "Oh Spike. I know I 'can' do that, but I can't." She got down off the couch and gave her assistant a firm, maternal hug. "This isn't a royal project. It's just my own pet project. Aside from my personal allowance I let the city counsel set, I'm not supposed to use the money in the coffer for personal endeavors. The rest is entrusted to me to use in the interests of the citizens of Equestria, not my personal projects."
She let go of the dragon and went to the speaker to talk to her test volunteer.
"I barely had an acceptable sample size as it was with six unicorns. I'll just have to shut the project down and save up a little to pay them better another day."
She then activated the speaker. "Thanks again for coming in, Lyra. But I can't work with only one test subject tonight. I'll still pay you for the full night, but you can close up and go home now."
With a few flicks of some switches, the machines that were recording data were shut off.
"OK, Spike. Care to join me for a breakfast for din-"
Suddenly a rumble in the sky shook the castle as a falling star streaked across the sky to the north.
*wwwwhhhheeeeefffooosh*
Running to her balcony, Twilight saw the star crash into the far side of the Everfree Forrest.
"..." she stood there with a blank face for a moment as the stirred wind from the falling star just blew by her unnoticed.
"You know what? No. I'm not going to beat myself up over it," She resolved herself as she went back to walking to the kitchen. "Even if the machines were on, nopony would believe any data from Lyra alone anyway. I'll just go look at the crash site in the morning."
She had barely left her laboratory when Spike burped up a letter addressed to twilight from Princess Celestia.
"Dear Twilight,
I apologize that this letter is written in haste, but it is of the utmost importance that you do not go anywhere near the fallen star that landed just now. I will explain further in person when I get the chance. I know you love to learn but please do not go anywhere near it nor allow your friends to do so until I've explained the situation to them."
Minutes before, in the Crystal Empire.
Sunburst sat at the table in the middle of the restricted section hidden well underneath the official restricted section of the Crystal Empire's royal library.
Princess Celestia paced around him, her normally polished demeanor long discarded. Discord was laying in the corner, with a sleeping mask on and a teddy bear. "I'm listening..." he muttered in his fake sleep.
"The Animus Mundi?" she barked her question at him much like a drill instructor.
Sunburst's glasses slipped as he tipped his head up and gave his answer bravely:
"The life force and residual energies of all living things in a world, interwoven and connected. Collectively it forms an energy field that can readily be described as the willpower, or some dare even say soul, of the world itself."
"Æther?"
"An energy that largely resides on a higher realm of existence than Equis, but can be drawn upon by many of our world's inhabitants such as unicorns and dragons and is the key energy used in most known magic," he prattled off from his memory as he confidently pushed his glasses back up to his eyes.
"Are they related?"
"While there is some overlap in end results, absolutely not. Æther is not connected to the life force of anything short of an automaton and has limited, indirect medical use. The Animus Mundi is capable of being used in ways that Æther cannot be used, such as the aforementioned medical applications. However, due to the inherit and overwhelming willpower that exists within the Animus Mundi, its applications must align with that will and thus said applications are far less flexible than Æther."
She quickened her pace around him as he spoke. "And Quintessence?"
"A folklore name for Æther before it was properly understood."
she asked again, "Quintessence?"
"The theoretical energy believed to come about with the use of both Æther and the Animus Mundi in a single task. No scientific evidence of this fusion of energies has ever been documented."
Princess Celestia stopped right in front of him and spoke in a wisper, "The winds of change cannot be stopped, but they can be guided. We must..."
"Be careful how we guide them, lest we change for the worst," he whispered back.
With this, she lifted her head back and asked one final time, "Quintessence?"
With a heavy sigh, he replied. "The element beyond elements, sometimes called divine or infernal energy depending on the disposition of the wielder. While faint on Equis, it is far more potent than Æther unit for unit. Its first known presence was when it was used in ancient times by the followers of gods that were foreign to Equis, and have since been banished."
"Its known wielders?"
"Yourself and the other Alicorns can use a trace amount in conjunction with Æther, granting you greater control and power. The Lord of Chaos, Discord. His resistance to Quintessence wielded by a native was reduced as a part of the magical contract he willingly bound himself to in order to be considered a surrogate native of Equis during the banishment of the foreign gods. However, while he is now weak-"
A dagger literally shot out of the draconequus's opening eye and levitated with its point right at Sunburst's throat.
"Correction: While he has willingly reduced his resistance to it, he can still utilize it in its raw state in a manner adept to the tactical terminology of a 'glass cannon' to achieve his chaos magic."
With this the dagger disappeared and the draconequus closed his eye again.
"Potential wielders?" Celestia continued without skipping a beat.
"Beyond the prior examples, Quintessence can only be used by natives of Equis who have great dedication and faith in a cause—such as the Pillars of Light in days past. Most users of it do not even know of it bein-"
*wwwwhhhheeeeefffooosh* a noise could be heard down the only stare case that led to the room, in spite of the muffling spells in place to keep noise from going in or out.
Discord shot strait up and wiggled wildly. Likewise every feather on the princesses wings went rigid when she saw this.
"Princess? Discord?"
"Session over. You pass. Welcome to level two. I have to go write Twilight," she rambled in haste before dashing up the stairs with Discord following behind.
He quickly dashed towards a high ranking member of the secret society.
"The taint is back," was all he spoke to the member as Celestia ran out of the anti-teleportation field and teleported. He then promptly followed suit out of the field and vanished with a snap of his claws.
In the hut she had made from the innards of a tree that a prior servant of the Animus Mundi must have planted for just such a purpose, Zecora meditated, and listened intently to the memories held within the Animus Mundi.
Pain. Great pain, pleading and suffering in the cries of the lands, waters, skies and deep earth was what she heard. Steadily, the pain became more sharply focused as the shaman braced and readied herself to let the image flow more fully through her. She could feel the pain of the trees being chopped down, the starvation and fear of the wildlife fleeing from ruined landscape after ruined landscape. She felt the choking of the life in rivers and oceans caused by the contaminants.
There were a few general chapters like this in the memory of the Animus Mundi. But all of the others were simply extinction level events in ancient times. Times from before the first servants learned to speak with the spirit of Equis. The Animus Mundi bore no ill will towards these events. The damage was done all at once and was over. The world would then recover over the eons and move on.
This particular moment that it was showing the Shaman, however, was something it feared. It wasn't a mere moment that hit it hard then allowed it to recover. It was a constant bombardment of damage, pain and suffering caused by a plague from outside. The plague came peaceably enough at first. Then, as soon as it had its tendrils around what it wanted, it yanked and consumed voraciously. Swiftly it would run over the next treasure trove of Equis's life blood, only to yank and tug again and again in an unending cycle of hunger. Torment never ending, never improving regardless what its servants tried to do.
Zecora had felt this a few times. She was aware of this entire story, but she was wanting to get a sharper picture of what the foreign energy felt like. She could tell it felt similar to a small number of native creatures but she couldn't quite place it. Many servants of the Animus Mundi simply accepted the tail as soon as their master was able to tell it to the end to them. They would then move on with their duties, satisfied with the vague description of the odd energy that was given, believing it to be merely a right of passage into a higher level of trust. Zecora, however, wished to delve deeper into it and recover some of the lost knowledge of that age.
Slowly, she meditated on this. She would get a slightly sharper image of that energy after making a small breakthrough every twelfth or so meditation. She felt like she was on a cusp of another breakthrough but the Animus Mundi was being particularly stubborn and she had no idea why.
She was about to give up and mark her wall for the forty second time since her last breakthrough when suddenly the sky lit up to the north.
With her eyes opened, she ran outside to see a falling star streaking across the sky and coming closer and closer to her.
Being so near, she probably would have been shuttering in pain from the noise alone.
That wasn't what was causing her to writhe on the ground, however. While one could normally simply let go of their link to the Animus Mundi and it would fade away on its own in under a minute, the shaman's connection went into overdrive from the other end. It screamed in agony with more crisp an image of the foreign energy than Zecora had ever dared dream of retrieving from it.
Just before she passed out, the shaman matched up that mental imprint burned into her mind with exactly one thing she had ever sensed with her own mortal senses: The energy being radiated from the falling star as it passed overhead.