It all happened so fast. One moment Sol, Twilight, and their guards had Tirek surrounded, and the next, said guards began dropping left and right. While he and Twilight both resisted the spell that had struck them, the guards weren't so fortunate as they didn't even get a chance to cry out in pain before being paralyzed and hitting the floor.
Not knowing what was happening, Sol hastily erected a barrier around him and Twilight. Having secured himself and Twilight, Sol then expanded the barrier outward, allowing it to pass harmlessly through the downed guards, but pushing Tirek back. As the barrier of light touched Tirek, grunted in pain as the searing light scorched him, ending the spell that had been disguising him.
Seeing Tirek's true form, Sol could now gauge how much stolen magic he already had by his body. Noting how far he had progressed by the size of his body and horns, and by the color of his coat, Sol raised his hammer and began pouring holy magic into, intending on weakening and capturing Tirek before he could become any stronger. However, as his hammer glowed with light, he saw that they had been surrounded by ponies who all fired blasts of green magic at the barrier in an attempt to break it.
"What are you doing?! Why are you doing this?!" Twilight asked, voicing her question before Sol could.
"I told you, Princess," Tirek grinned, "I'm not the one who's surrounded."
"You... did you manipulate them into betraying us like you did Discord?!"
"Of course he didn't." Twilight and Sol looked behind them and saw the green unicorn mare from earlier approach the barrier, chuckling along the way. "Actually, it was I who approached him."
"You?"
"Yes. You see, I needed his help for my plan to succeed, and in return, he's free to have fun and seek his own revenge. Now I can finally get my revenge on Starlight Glimmer, and as a side-bonus, I'll also rule as the new Queen of Equestria!"
"'Revenge on Starlight'? 'Queen of Equestria'? Just who are you?!"
The mare brought a hoof up to her chest and gasped in a mocking hurt.
"You mean you don't recognize me?" she faux gasped. "Oh, I'm sorry. Let me just change into something a little more appropriate."
Though confused at first, Twilight and Sol both knew what the mare meant as soon as green flames engulfed her body.
"Chrysalis?!"
Now in her true from, Chrysalis took a moment to laugh at their expressions.
"Oh, the looks on your faces are priceless!" As Chrysalis laughed, the rest of the ponies around Sol's barrier burst into green flames, revealing that they were all Chrysalis' changelings. "By the way, I suppose I should thank you two. Not only did you let us and a train full of my changelings just walk on in to your gilded city with open hooves, but you also did us a huge favor by scattering your guards and Wonderbolts. Spreading out your forces like that made this whole thing sooo much easier for us."
Twilight's eyes widened in horror as she realized what this meant. It was bad enough that Tirek was there in Canterlot, but now with the revelation of Chrysalis being involved, everything just fell into place. The reason why Tirek was able to hide for so long without anypony spotting him, their suspicions about the guard captain in Las Pegasus, and Tirek's words all made sense now. It didn't help her any either how calm Chrysalis' changelings were being with Tirek so close to them, and vise versa.
"So," Twilight attention was brought back to Chrysalis as she spoke, "am I to assume that Starlight Glimmer is in the caste with the others?"
"I'm not telling you anything, Chrysalis!"
Despite the harsh glare she was receiving, Chrysalis found it more amusing and began to chuckle.
"Poor, naïve princess. You make it sound like you have a choice."
Calmly, Chrysalis approached Sol's barrier and raised a hoof to it, confusing both Twilight and Sol. However, to both of their surprise, the moment her hoof made contact with it, the barrier began to fade away from the spot she touched it.
"But how?!" Sol shouted dumbfounded at how his barrier could be so easily dispelled by just the touch of a hoof.
"Ahh. Don't you remember?" Chrysalis cooed. "After all, it was your daddy who gave me this gift."
Confused, Sol took a second look at Chrysalis. As he did, he noticed several glints of light coming from around her neck.
"Kind of ironic, don't you think? Your father's gift to me will be the key to help bring you, Equestria, and everypony to their knees."
As Chrysalis got closer, Sol spotted three black rocks hanging from a black string tied around her neck, along with sensing the familiar magic that it held.
"... no."
"Yes. It took me a while, but I was finally able to collect enough of my throne's shards after my defeat to make a necklace for not just myself, but for each of my changelings!"
Sol's head snapped around as he saw the other changeling calmly approaching the barrier.
"But how is that possible?!" Twilight questioned. "The magic in your throne prevented the use of non-changeling magic in a massive range, so if those really are the same stones, then why aren't they doing that now?!"
"You mean you really don't know?" Chrysalis pouted. "And here I thought you were the smart one."
Twilight furrowed her brow. "... excuse me?"
"I suppose I'll just have to spell it out for you," Chrysalis mockingly sighed. "You see, since these shards are so small, they can only hold a fragment of the magic my throne had possessed. As one they are more powerful, but fractured like this, their magic reach is very limited, but still just enough to protect those who wear them. How else do you think I could trust Tirek to not steal our magic? If it weren't for these, he probably would have betrayed us by now."
Oh, I had thought about it, but you and your changelings are still useful to me... for now, Tirek mentally commented.
Sol growled at their situation. His first thought was to fire a beam of magic at Chrysalis, but with that necklace, she could just face tank it without losing that smug smirk on her face. With Chrysalis and her changelings all but walking through his barrier, Tirek waiting behind them, and having a hoofful of paralyzed guards down, Sol was left with little option.
Using his magic, Sol forewent his magical barrier and created a spiked-dome of stone that erupted from the ground around him, Twilight, and their guards, buying them some time.
"Twilight, I need you to teleport these guards to the castle and tell mother what's going on here."
Twilight looked over to Sol. "What about you?"
"I'm staying."
"What?! No! I'm not leaving you here alone to-"
"There's no time to argue, Twilight!" Sol's ears flickered at the sound of stone cracking from the magical bombardment outside. "Listen, given the current situation, I can't fight them and properly protect these ponies at the same time. I'll keep Tirek and Chrysalis busy while you get these ponies out of here and tell mother and Aunt Luna what's happening. With those two here, the damage to the city should be drastically reduced, but we'll also need help to contain Chrysalis' changelings that are running loose in the city."
Twilight winced as a blast of magic cracked open a small hole in the stone wall. She didn't want to leave Sol to fight Tirek and Chrysalis on his own, but she also knew that she was the only one of them who could teleport the guards to safety and warn Celestia. She could also ignore Sol and take him with her, but apart from betraying his trust in her, Sol also made a point. If he were to stay and keep Tirek and Chrysalis occupied, then the worse of the damage would at least be contained to just this area.
Having reluctantly made up her mind, Twilight stepped forward and leaned up to share a quick kiss with Sol.
"Please be careful, Sol."
"I will. Now hurry."
With a worried look, Twilight lit up her horn and a few seconds later, she and the guards were gone. Now alone with nopony in danger of getting in the way, Sol re-shaped the stone wall into stone spears, and launched them at the surrounding changelings and Tirek. Tirek didn't seem to mind too much as he grabbed and swatted the spears out of the way with his hands, while Chrysalis and her changelings had to dodge out of the way. After all, they may have been shaped and launched by magic, but in the end, they were still lethal projectiles made of stone.
Distracting them with his attack, Sol sunk into the ground and burrowed over to the nearest changeling. A moment later, he burst from the ground and swung at the unsuspecting changeling with his hammer. Though the changeling didn't see the blow coming, some of the others did and used their magic to pull him out of the way of Sol's strike, causing his hammer to hit the ground with enough force to cause a small crater.
"What did I tell you?! Keep away from him!" Chrysalis barked, seeing her changeling almost get squashed into paste.
Obeying their queen, the changelings all took to the air to prevent any further sneak attacks from Sol. However, while the changelings and Chrysalis were all out of Sol's reach, Tirek wasn't.
Taking advantage of this disadvantage, Sol burrowed underground and headed straight for Tirek. Having not seen any of Chrysalis' shards on him, Sol charged his hammer with light as he approached. Though Tirek knew what was coming, he couldn't do much to dodge it since he didn't know where Sol would attack from. He found out a second later when Sol burst from the ground directly in front of Tirek and swung his hammer in an upward arc. Surprised, Tirek couldn't react in time as the light-imbued hammer connected with his chin with a resounding boom. Roaring from being struck by Sol's light magic, Tirek stumbled back a few steps as he held his sore, light-scorched jaw.
Having temporarily stunned him from his strike, Sol charged up his horns to fire a beam of light at him, but his channeling was abruptly interrupted when he was hit from several different directions by blasts of green changeling magic. While it didn't hurt him thanks to his armor and the thickness of his Scaleless Draconic hide, it did get his attention and remind him that he and Tirek weren't alone. And with them providing support like this, it would be difficult for Sol to be able to defeat Tirek.
Changing his target, Sol flapped his wings and turned his attention to the changelings. Blocking a few incoming blasts with his shield, Sol spotted the nearest changeling and proceeded to fly after it. Unfortunately, due to his already slow flying speed, Sol couldn't catch up to the fleeing changeling. Instead, as he flew after it, the others began firing spells at him from a safe distance, forcing Sol to dodge and block the incoming attacks. Finding that chasing this one was becoming more trouble than it was worth, Sol switched over to another changeling and flew after it. Like the one before, Sol was once again outrun by its faster flying.
While he was distracted by the changelings, Sol didn't see Chrysalis coming until her hooves collide against his armored back, the surprise force causing his wings to lose their beat and send Sol falling with Chrysalis on top of him. Growling at the surprise attack, Sol spun around in mid-air and took a swing at Chrysalis, who was charging her horn to restrain Sol in changeling gunk, but saw it coming and was forced to instead push Sol away with her hooves before his hammer could hit her. Having missed, Sol contorted his body around to land on the ground with a safe but heavy thud that cracked the road beneath him. As he straightened himself, he saw a shadow looming over him and instinctively raised his shield up above his head. A second later, he felt a massive impact strike his shield, and glanced up to see both of Tirek's pony-sized fists pressing down against his shield. Frowning, Sol light his horns and fired a blast of light magic at Tirek, only for it to be harmlessly intercepted by a changeling.
Seeing his magic having been nullified again, Sol decided that a change tactics was in order. If magic wouldn't hurt them, then like with the stone, perhaps something else would. And so, Sol took in a breath of air before unleashing his light breath at the changeling swarm around him. Even if his multi-colored breath attack was heavily imbued with light magic, it was still fire at its core, so the changelings' necklaces wouldn't be able to fully protect them from it. A fact that had been made apparent when he saw the changelings promptly dodge out of the way, while Tirek raised a barrier around himself.
Good. So they do fear it.
Smirking at having another way to attack Chrysalis and her changelings at a range, Sol raised his shield and took a defensive stance. If they wanted to attack him with spells, then he would just block them with his shield or a magic barrier. And if they wanted to break through his defenses and actually hurt him, then they'd have to come within the range of either the flames of his light breath, the stone beneath his hooves, or destructive force of his hammer.
Twilight teleported in the middle of the throne room with the paralyzed guards. Wiping a drop of sweat off of her brow, Twilight was met with the worried looks of Celestia, Luna, and some guards who were rushing over to aid their fallen companions.
"They'll be alright. They just got hit with a paralysis spell. Just give me a moment and I'll have them cured," Twilight said, powering up her horn to dispel the magic placed on them.
"Twilight, what happened?" Celestia asked as she and Luna walked up to her and began curing the guards as well.
"You're not going to believe this, Princess, but Tirek is here! In Canterlot!"
"He's what?!"
"It gets worse. Turns out that Chrysalis is here as well, and she and Tirek seem to have joined forces."
Celestia's eyes went wide at the news, while Luna's narrowed into a glare.
"This is not good," Luna grimaced. "Those two together are going to be a real problem."
"And where's Sol?" Celestia nervously asked.
"Sol stayed behind to try and fight Tirek and Chrysalis," Twilight informed them. "I tried to talk him out of it, but he was adamant on staying. He believes that while he has those two occupied, he can minimize the damage while we search for Chrysalis' changelings roaming Canterlot."
"How many are there?"
"A lot. According to Chrysalis, every one of those ponies who were aboard that train from Las Pegasus were all changelings. What's worse is that Chrysalis got ahold of the shards of her old throne, and then turned into necklaces for herself and each of her changelings."
"You mean the throne that drains all non-changeling magic that Starlight Glimmer and her friends destroyed?" Luna asked for clarification.
"Yes. The shards have lost much of their magic, but they still retain enough to protect whatever's wearing it."
"But it shouldn't be a problem for Sol. If he could get his claw on it, he could destroy the shards with ease."
"While that may be true, Luna," Celestia spoke, "you have to remember that Sol isn't that fast of a flyer. He lacks speed and mobility for high durability and strength, so he may not be able to get close enough to actually get ahold of the shards."
Luna nodded. "Then he shall need our assistance immediately. I will go out and support Sol while you deploy the guards."
"Alright. Just remember, Luna, that you must restrain yourself."
"I know, Celestia. I promise I won't-"
"Your Highnesses!"
Everypony's attention was drawn to Captain Iron Guard as he ran into the throne room, levitating three scrolls alongside him with a panicked look on his face.
"Yes, Captain?" Celestia calmly called.
"Your Highnesses, I have just received grave news that requires your immediate attention. First, we have received multiple reports of Tirek having been sighted by the train station with Queen Chrysalis, along with a small swarm of changelings. Sol is currently engaged with them, and seems to be holding his own for the moment. I have already awakened and informed Captain Night Wing, and we have deployed both the day and night guards to help assist him in the battle."
"Thank you, Captain, but Princess Twilight here has just informed my sister and I of the situation. We have also been informed that the train that had been carrying the refugees from Las Pegasus were in fact Chrysalis's changelings, and that they are currently running amok in the streets disguised as ponies. They also each carry a stone that protects them from all non-changeling magic."
The captain looked like he was in thought for a moment before giving a curt nod.
"It may not be as hard to find them as we believe. If my unicorns can do a magical sweep, we can pinpoint who the disguised changelings are since they won't be affected."
Luna smiled. "A clever plan."
Iron Guard bowed. "Thank you, Princess. However, I'm afraid there's more." He unfurled the three scrolls he held in his magic and presented them.
"What's this?" Twilight asked.
"These are reports from Fillydelphia, Baltimare, and Manehattan. Each of them report that they too are under heavy attack by changelings, and are requesting immediate support."
Twilight, Celestia, and Luna all looked over the reports in horror. None of them had suspected that an attack on Canterlot like this would in fact just be a piece of something of this scale.
"So Tirek's and Chrysalis' sudden appearance in Canterlot is not a coincidence," Luna muttered.
"But how did Chrysalis manage to produce so many changelings that she could attack four major cities all at once?!" Twilight exclaimed.
"I don't know, Twilight," Celestia said, "but if these reports are true, then what we're dealing with here is not some desperate attack, but a well-coordinated invasion."
Twilight's face paled. "I-Invasion?!"
"Yes." Celestia turned to Twilight. "Twilight, I want you to tell your friends and their families to all gather in the throne room. It will be safer for them to all be in the same place where we can keep a close eye on them, my sister and I included."
"But what about my parents?!"
Iron Guard stepped forward. "I have already sent a squad and chariot to pick them up and escort them to the castle. They should be arriving momentarily."
Twilight let out a sigh of relief. "Thank you."
"As relieving as that is, our overall situation is still dire," Luna reminded them. "Equestria's major cities and capital are being invaded, and as loathed as I am to say it, we don't have the numbers to aid everypony. Most of the Wonderbolts and scouts are still out patrolling, and if Celestia and I enter the fray, there would be a very real risk of great collateral damage, myself especially."
As they talked, they continued to cure the paralysis magic on the guards. Once the last of them were cured and left to help secure the castle, Twilight turned to the throne room doors.
"After I tell my friends, I'm going back out there. Sol needs to be told what's going on."
Sol's magic washed over his face as he healed the cut on his cheek. While he was holding his ground rather well, he couldn't get much done either. Despite managing to get a few good hits in on Tirek, Sol hadn't otherwise done much damage. Chrysalis and her changelings had kept their distance from not just Sol, but also the ground and buildings after some stone spikes nearly hit a few of them. Since then, Sol's been doing what he could to keep them occupied, all the while being periodically taunted by both Tirek and Chrysalis.
"What's the matter, whelp?" Tirek goaded. "Why not unleash your full power? What? Are you afraid you might accidentally destroy this city with your unleashed power? Cause enough damage for it to fall off the mountainside? Create a rockslide from a stray shot of magic? Or, maybe you're just too weak to fight us? Mmmmm. Now that I think about it, you seem weaker than I remember you being over a thousand years ago. This time of peace must have made you soft."
Sol glared at the two. "Not soft enough to fall to you two."
Chrysalis laughed. "Maybe not, but if you can't beat us, then we win. After all, if you're here, then how can you hope to protect your precious little ponies from my changelings?"
Sol gritted his fangs as Tirek joined in Chrysalis' laughter. However, it was short-lived as a purple beam of magic was fired from the sky, colliding with Tirek's back in an explosion that forced him to his hands and knees. Looking up, Sol saw that the beam had come from Twilight, who'd teleported in above them and took advantage of the situation to land a hit on Tirek.
"Twilight, what are you doing here?! It's dangerous!" Sol exclaimed.
"I know, but it turns out we've got another serious problem on our hooves," Twilight worryingly said. "At the castle, we received word that changelings were attacking Fillydelphia, Baltimare, and Manehattan!"
"So they managed to get a message out to you after all," Chrysalis said, clearly not worried by this news. "Oh, no. How will we ever deal with this?"
Disturbed by the news of other cities having fallen under attack as well, Sol clenched his jaw and growled. It was bad enough that Tirek and Chrysalis were in Canterlot and working together, but with this news, Sol was made aware that at the rate things were going, not only would Equestria fall, but all of it's ponies would be at the mercy of Tirek and Chrysalis.
And so, it was with no shortage of shame or regret that Sol sighed heavily as he came to a decision.
"... Twilight, teleport us out of here."
Not bothering to question it, Twilight quickly teleported herself and Sol away before Tirek, Chrysalis, or her changeling could stop her. Appearing in the throne room in a flash of light, the two were met with their friends and respective families, including Twilight's parents, who quickly ran over to hug their daughter.
"What's goin' on out there, Twilight?" Velvet asked as she fretted over her.
While Twilight was busy with her mom, Sol sadly shook his head and walked over to Celestia and Luna.
"Twilight told me what's happened."
"And she is correct," Celestia said, noticing the bloodstain on his coat and looking over it in worry.
"I'm fine, mother. I healed it already."
"Hold on a second! Did he just call Princess Celestia 'mother'?!"
Apart from cringing, Sol ignored the voice of the annoying pegasus stallion with the messy mane bun, knowing that he had bigger problems to worry about right now.
"... I'm sorry to say this, mother, but... I believe the time has come."
Celestia's and Luna's faces both turned serious, knowing what Sol's words meant.
"Are you certain about this, Sol?" Celestia asked. "This is a massive decision that will affect all of Equestria."
"I am," he nodded. "Canterlot and three other cities are under attack and outnumbered by enemy forces, and those are only the ones we know about. For all we know, there could be other places that are being attacked as we speak and we may not even know it. I never thought I'd actually have to say this, and I wish I didn't have to, but if there was ever a time, it would be now. Not even you or Aunt Luna can rightfully oppose at this point, mother."
"Sol, what are you talking about?" Twilight asked. "You said that the time has come, but for what?"
Sol looked back at Twilight and the collection of ponies with a look of shame and frustration.
"To open the portals. We're evacuating to the Underkingdom."