Twilight never remember being this miserable, and it was for something she had never thought would be possible.
She had finally called out 'Cadance' on how awful she was acting to everyone, but nopony had believed her. Shining Armor had all but disowned her, her friends had abandoned her, and her mentor...
She had never seen Princess Celestia more disappointed, not even during the Lesson Zero incident had she looked so disappointed. "You have a lot to think about," she had said before leaving with the others.
Where had it all gone wrong? This was supposed to be a joyous occasion. Her brother was marrying Cadance, her old foalsitter and the closest thing Twilight had to a sister.
Now she had lost it all. Lying on the steps of the altar, she let her tears fall. For a moment, she lay like that, before she felt a hoof pat her on the head. Looking up, she found Cadance giving her an odd look.
It was too much for Twilight. "I'm sorry," she choked out.
For a second Cadance said nothing, then her face twisted in a scowl. "You will be!" She said in a tone that didn't sound like her at all.
At once her horn ignited in a green aura. Twilight watched in shock as the magic spread around her in a wall of green flames. Cadance's smile became so twisted it wouldn't have looked out of place on Discord.
But there was nothing Twilight could do as Cadance began to walk away. She was surrounded, and it felt like she was sinking into the ground as the flames covered all of her.
"No! It will not end this way."
Twilight jumped as a voice she didn't recognize entered her head. But it felt like she know it. Deep down.
"Remember me Twilight. Remember the time we had."
And Twilight remembered. She remembered the time that she felt had always been missing from her memories like a nagging tooth. It all came back. "Penumbra?"
"Yes. I'm sorry it took this for you to remember. But it was a side effect of the Soul Bonding. I once said I would come to you in your time of need. That time has come."
Twilight didn't know what she meant, but she hoped Penumbra had an idea as she was almost sunk into the floor now. "What are you going to do?"
"End this farce."
Twilight said no more as she felt her horn ignite in a blaze of power. It felt like her magic surge as a filly, but this time it felt right. Twilight smiled as she let go of her control as her eyes blazed white.
***
Cadance left the meddling fool to her fate. That brat had almost ruined everything. Luckily for her, ponies were far more stupid and blind than she had thought. Where Twilight was going, she wouldn't be bothering anyone anymore.
If she was lucky, maybe she would even get rid of her other guest down there in the caves.
She was almost to the door when she felt the backlash of magic from behind her. Turning around, she watched in shock as her spell sputtered and failed, the green flames replaced with flames of black. Inside them, a new form began to take shape, as a shaft of black light shot upwards.
***
All across Canter Castle, everyone jumped as they felt the release of magic, followed by a wave of fear. No one knew what to make of it, but the Mane 5, Spike, Princess Celestia, and Shining Armor all turned back to the Ball Room.
Shining's Royal Guard training overcame the mind control he was under. Something was wrong, and whatever else had happened between them, his love for Twilight overcame his earlier anger. She was at the center of this.
Princess Celestia meanwhile was both concerned for her student and worried. She knew this feeling, but that wasn't possible. She hadn't felt this since...
"No. It can't be her. How can she be here?"
***
Far away, another pony too felt the release of magic, and for the first time in more years than she now wanted to admit to, she smiled a real smile, even as she added a bit of her own magic to what was happening in Canterlot.
"Good luck Penny."
***
When the flames died away, Cadance's shock rose as the very last pony she ever expected to see stepped forward. Alongside that came another sensation she was unused to.
"You? How are you here?!" She asked with fear and horror.
Penumbra stretched her wings for all they were worth as she took stock of what was in front of her. She knew that aura anywhere. But to see it here like this? Either it spoke of gross incompetence on Celestia and Luna's part, or something else was going on.
"I have every right to be here creature," she replied, taking pleasure in the look of horror she was getting. "Far more than you do at least."
Cadance only replied with a spell blast to Penumbra's face. Her smirk dropped when Penumbra walked right through it. She gave the insect credit. There was considerable power behind that blast. It might have even worked on somepony else.
"You know. I was hoping my first time back in Equestria after so long would've been under better circumstances. But stopping you will have to do," Penumbra replied as she spread her wings and dropped all restraints on her Aura of Fear.
Even as she did, the door to the room burst open and the Mane 5, Spike, Shining, and Princess Celestia ran in. Immediately, all felt the full force of the Aura Penumbra was projecting.
Only Celestia knew it. But to see her here and in all of her glory was more of a shock than anything had been for a long time.
The others on the other hoof? They were on their knees, their bodies close to the ground. All of them were trembling, their faces all bearing the same expression. Pure and absolute fear. Not even Applejack or Rainbow Dash escaped it. They couldn't even try and hide it.
Celestia felt sorry for them. No mortal was ever meant to be in Penumbra's Aura when she had it at full power. Not even she could for long, and they weren't even being targeted.
Then her eyes drifted to Penumbra's cutie mark, and her heart sank at what she saw. "Oh, Twilight. Why?" She whispered as her tears fell.
It was a combination of Twilight's and Penumbra's own. Half Twilight's starburst and half Penumbra's pentagram.
Penumbra finally noticed them. Her frown deepened as she beheld the ones who had left this devolve into what it had, but it was not her place to take them to task about it. She briefly wondered where Luna was in all of this. She would've felt it by now. A detail for later as she turned back to Cadance. "Reveal yourself," she commanded as a beam of magic jumped from her horn and struck the mare.
Immediately she was engulfed in green flames that soon revealed her true form. Penumbra was not shocked to see it who it was, even as everyone else was still confused. "Chrysalis. Why am I not surprised? Only you of your sisters were ever stupid enough to think you could get away with anything like this."
Chrysalis spat. "Fools. This world is our by right. These cattle are less than nothing to us. To me. Equestria is weak, ripe for conquest. Equus will fall before me."
"And if I stand before you?" Penumbra asked, already preparing a spell.
Chrysalis sneered. "Then I will remove you as well. You've made us hide in the shadows for far too long. No more."
Penumbra nodded as the spell fired at Chrysalis's hooves, manacles locking around all four of them. "That is all I needed to hear." She turned to face Celestia. "I am not asking for your permission Celestia. I know what your thinking."
Celestia gritted her teeth. "She attacked us Penumbra, replaced my niece, and who knows what else. She must face justice for that."
Penumbra laughed an ugly sound that made everyone's ears hurt. "And what kind would that be? Yours? You are too forgiving Celestia. You always assume the best, and never prepare for the worst. This whole debacle is a perfect example of that."
Celestia glared at her. "And what is that supposed to mean?"
Penumbra sneered at her. "You know exactly what I mean. But I'm not the one you have to apologize to," she said as she looked at her cutie mark and smiled. "You know what Twilight has done, how I'm here. I hope you know why she would."
Celestia nodded, as much as it hurt her inside. At the same time though, she couldn't help but be proud of her student.
Penumbra finally allowed her Aura to return to normal. All at once, everyone felt a wave of relief wash over them. Fluttershy was the first to speak as she looked at Chrysal. "So, what happens to her?"
Penumbra frowned once more. "She has broken Changeling Law. My law. She will be punished and the Hive Council will hear of this. What happens to her hive after that is up to them."
"What about Twilight?" Rarity asked.
Penumbra smiled. "She is fine. She is still with us. But I am in the driver's seat, so to speak."
"What the hay is that supposed to mean?" Applejack asked.
"It is complicated, but right now we have another problem to worry about," Penumbra replied. They had to hurry too. She and Twilight could not keep this up much longer. That they had lasted this long was something of a miracle.
She turned her gaze back to Chrysalis. "Where is Cadance?"
***
Hours later, after Chrysalis had finally revealed where she had hidden the real Cadance and a Royal Guard squad had been sent to bring her home, everyone was once again gathered in the Ball Room.
Chrysalis had been condemned to eternity in Tartarus, and her hive had scattered to the four winds outside Canterlot's shield. No one had said anything about it, though Celestia was still somewhat sore about the whole thing.
Luna had finally shown up partway through all of this. To call her and Penumbra's reunion awkward would be like calling Pinkie Pie hyper: a massive understatement.
***
Luna wasn't sure why she had been called away at this time of day. As far as she knew, there was nothing that needed her to be present. The only major event of the day was the Wedding Rehearsal being held in the Ball Room.
A wedding she was not planning on attending. Not to spite the bride and groom of course. But her social skills were still not fully up to date, and a wedding would be a perfect chance to make a fool of herself.
But more than that. She barely knew Cadance at all. Her niece. It had been a shock at first when they had first met, to find that she had more family now. Cadance of course had always made an attempt to get to know her better, but Luna had always brushed them aside.
It only hit her how rude she was being when the wedding invitation had come to her. She hadn't even known Cadance was engaged. At that moment, she had felt broken inside that she had rebuffed her niece's attempts to befriend her.
So she had declined, afraid she had lost any chance. And now Cadance was soon to start a new family and all that came with that. She wouldn't have time for Luna.
She had planned to attend the Reception of course to congratulate the new couple. For no matter what, this was an occasion for clebration no matter what she thought.
Whe she had been called now she didn't know, but maybe it had something to do with the massive release of magic she had felt earlier. If it was, then she was worried.
"It can't be. She can't be here. It's not possible," she thought, for she knew that magic well.
When at last she reached the Ball Room and entered, she was greeted by the very last pony she ever expected to see again.
"Hello Luna," Penumbra said icely.