"NO!" Celestia cried, adding to the cacophony of shouts and howls from the ground.
She flew down as the burning mass landed only a few yards in front of its intended target.
"Twilight!" she whimpered, hoping beyond hope that her student had survived the blast.
Frantically brushing at the flames with her magic, she attempted to smother the fire only to have it flicker and dance as if amused by her futile attempts to contain its fury.
Out of the flames leapt a wolf's blazing form. For a second she thought her student to be engulfed in the flame, but soon the truth became apparent: the flames were not licking up to her, the scorching heat and inferno were emanating from her.
This realization came a second too late as the burning wolf howled and a second realization hit her: the wolf wasn't fleeing from the flames, she was coming at her.
"Run!" Twilight shouted to her wolves.
The pack recognized that there were times to follow the leader, and there were times to disobey their orders. When the leader is weak and injured, ordering you onward and to leave them to their fate; you respectfully break orders and help them. When the leader you expected to be weak and injured has manifested an affinity for the scorching flames of the sun, and stands prepared to do battle with a legendary propagator of genocide, you promptly do what they say.
The wolves stalled only a second to collect the strange blue and striped ponies before bolting at full speed in the direction the striped pony pointed.
Behind them they could hear the unmistakable sounds of battle.
"Mistress!" Screw Loose cried, "We have to go back for Mistress!" Flailing in the grip of the wolf that was carrying her, futilely trying to fight free.
"If you wish to follow her will,
You will stay calm and still.
Towards Canterlot we must flee,
I have no doubt she'll follow shortly." Zecora said. Her words calmed the frantic mare, ending her violent struggle. Only the wolf that had scooped her onto his back could hear the subtle quaking of the Zebra's voice.
Before the burning wolf could tackle her, Celestia took flight.
"What madness is this?" The alicorn stared abhorrently at the growling beast below her.
The sound of softening yips alerted Celestia to the now absence of the wolf pack.
A look to the beast and a moment of hesitation plagued her before she turned and set herself in a dive towards the sounds of the fleeing wolves.
There was a bark from behind her and a flash of light. Before she could process why, she was suddenly sent tumbling.
Fumbling to regain orientation she threw her wings open and glided back to the ground.
In her path lay a mutely purple transparent barrier.
Realization washed over the Solar Princess as she turned, glare hardening on the burning wolf.
"Lower this barrier right now."
The wolf stood firm.
"Using magic? Holding me here while those beasts escape? Knowing that I wouldn't harm the visage of my student? You're a crafty one, whatever you are."
This time it was Twilight who had to dodge as Celestia swooped down at her.
"...But now your trick is over and I can see you for what you are! Mark my words beast I'll track down and destroy those monsters..."
She swooped down again, this time firing a magical blast at Twilight, which she just barely dodged.
"-And then I'll deal with you properly."
Twilight was just narrowly managing to dodge the Princess's attacks, but was finding the real struggle to be the one inside her head.
From the outside an objective observer would probably say that Twilight was a brave pony. Having faced down gods and demons, armies and monsters, evil queens and dark kings, most would probably say she was fearless.
...but she knew this was not the case. She knew she was afraid. She was always afraid. It was instinct to be afraid. When she charged Nightmare that night it was not that she had conquered fear, she had merely overcome the flight instinct associated. She had conquered the single most primal instinct of ponydom. She never ran.
But now, as she made each narrow leap to safety she felt something new. Her biology was presenting her with a new instinct; a new option in the face of fear. One that she was unaccustomed to fighting. One that had a draw she was finding harder and harder to suppress.
Whereas she had learned to overcome her desire for flight, she was unaccustomed to managing, and noticeably losing her grip on her desire to fight.
"Princess!"
The call interrupted the one sides exchange between the alicorn and wolf, but did nothing to lessen the tension surrounding them.
Celestia laid off her offensive for a moment, turning to find that the guard contingent had caught up, edging up to the barrier armed and ready for war.
"Go after the Timberwolves!" she shouted to the stallions, "They fled into the forest in that- GAAAAH!"
The guard watched in helpless horror as the hoof raised to point the way was suddenly grasped in the jaws of a pouncing monster.
The stallions instinctively slammed into the barrier as if sheer force would rend it. Their attempts to reach their monarch proved futile though as the barrier refused to yield.
Dragged to the ground, the burning creature and monarch began to wrestle for dominant position, all while blood flowed out of the injured leg and through the teeth of the berserker wolf.
When it finally appeared that the wolf had gained dominant position, a hard buck from below broke them apart and sent the beast sailing into its own barrier.
Celestia rose. "What did you possibly hope to accomplish beast?" She spat the words, glaring contemptuously at the wolf as it stumbled to face her. "Why do you even flee? Nightmare is gone! What purpose do her golems still have to serve? Why do they not just lay down and wither to dust?"
The staggering wolf had regained her footing and shakily squared off with Celestia once again.
Celestia could see the wolf taking quick glances back and forth between her face and the leg her healing magic had already begun to fix.
"Do you now realize how futile your efforts are? While you managed to let those beasts escape for now, there is nothing you can do to stop me! To stop the inevitable!"
Celestia could see something in the beast's eyes change at her call.
It's legs tensed as it lowered its position.
This is what she was waiting for. She charged her horn for her ace in the hole. All she needed was for the beast to leap within range and she could finally end this mess. She lunged, prepared to meet the wolf in flight.
...but it didn't happen.
The wolf leapt and she lunged in turn, but no contact was made. It took only a millisecond to happen but a woefully long second for her to process.
The instant before impact, before contact was made and she could use her spell, the wolf disappeared.
After a painfully long second she realized that the barrier was gone too.
...She had been tricked! The wolf had not been tensing for a deciding blow, it had been preparing to flee.
Celestia's legs gave out from under her.
"Fan out!" the commander shouted to his stallions as he sprinted to the fallen alicorn's aid, "It attacked the princess! Find the beast and kill it!"
"NO!" Celestia shouted, "Withdraw!"
"But princess! You almost finished it! We need to press the advantage you've made and kill that beast while it's weakened!"
A fire ignited within the alicorn's eyes that made the battle-hardened captain wither beneath it "I was not going to 'finish it', I was going to knock out my faithful student so that we could HEAL HER!" she turned away from the stallions, hiding her face behind the ethereal flow of her mane.
"WITHDRAW NOW!" The command was punctuated with a flash of magic as she teleported away, fleeing the scarred landscape and audience of thoroughly terrified stallions.