"There are only so many places a snake like him could hide," Celestia said. She was standing over the largest map of Equestria that her forces had managed to dig up and it now lay across five tables that had been placed side by side in the center of the library. Trunks stood on the north side of the map with Pinkie and Rainbow at his sides. Celestia stood on the south side, her face gazing over each and every inch of the map.
"He can make himself into smoke and shadows. He could technically hide wherever he wants," Rainbow reminded the princess. "If I was him, I would order my forces around from the shadows and only come out from the darkness only if I absolutely had to."
"Thank you for keeping me grounded, Rainbow Dash, but there is one very important fact about Sombra that you neglected. His ego," Celestia said with a smirk. "The only thing larger than Sombra's forces is his ego. He won't want to be seen as a coward nor will he allow us to be beaten unless he is there. So he will be somewhere where he can be both close by, in case the moment comes to strike me down, but also a place secure enough to ensure his own survival. But there are numerous places across this land where that could be. I've marked them for all of you."
Trunks leaned on the table and glanced over the map, finding six red X's in various locations. The locations meant nothing to him and a quick glance at Rainbow Dash showed that her mind mirrored his own confused thoughts. "Um, Princess, if you don't mind me saying, these marks are just random locations. There's nothing in any of these places that I would even begin to consider being able to repel an attack by our forces."
"That is because you have not ruled over this land for nearly a thousand years like I have," Celestia replied with a bitter smile, clearly not happy at the reminder that she was only getting older. "These six locations are each magic hotspots, places where the natural magic in our world is at it's strongest, increasing the magical strength of any magic user that is within the area of its effect. I take it that you notice that these six locations are also where Sombra had brutal and decisive victories over us?"
"Actually...yeah, I remember fighting here. And here," Pinkie pointed out as she jumped onto the table. "And here. And here!" she practically sang as she hopped from X to X, a small giggle escaping her lips each time, before she came to the final location and dead stopped. Her mane deflated and she hung her head in sorrow. "And here. I will never be able to forget this place."
Rainbow joined Pinkie up on the table and placed a wing over her, staying silent in respect to the fallen. Trunks didn't need any explanation for the scene, so instead he turned his attention back to the princess. "So which of these places do you think would be the most likely place for a king like Sombra to hide? I can search all of these places, but there is no guarantee that he won't escape me. He seems like a slippery one."
"Oh he is a slippery one. In fact, I was more or less hoping that you would use that incredible power of yours to simply nuke these places from orbit," Celestia admitted with a bitter smile. "Even if he could react in time, I've seen how large your explosions are. He would be ash before he had the chance to escape. Not to mention the massive amount of light your attacks generate would prevent him from using his shadow form to escape."
"That would be the smartest plan, if it wasn't for one flaw," Trunks pointed out. When Celestia raised an eyebrow, Trunks closed his eyes and reached out with his senses to the areas where Celestia had marked in the real world. "Yes, I can sense hundreds of mind controlled ponies standing guard in each location, ready to fight to the death in his name. So the nuking him from orbit is a no go."
"Trunks, as much as it pains me to admit it, there is no way to break the mind control on those ponies," Celestia whispered with a pained look. "We have captured plenty of them and tried multiple times to break them free of his control, but...they are all but dead already. At this point, all we can view them as are his army. I wish there was another way. But..."
"My answer is still no," Trunks replied coldly. Celestia looked at him with confusion. "I am not going to kill anyone who is not evil. I've seen so many innocent die at the hands of the forces of evil before. I refuse to let anymore die. Not while I can help it."
"Then we are at an impasse, for as you said, Sombra could escape from you if you showed up to capture him," Celestia reminded Trunks. "But I know that look in your eyes. That look tells me that you have something else, something far more crafty up your sleeve, do you not?"
Trunks let a smile cross his face. "You said that you had some of his soldiers imprisoned here, right?" Trunks asked. "Bring one of them to me. I think I can do a little more than just fly around in circles hoping I find him."
Celestia nodded to her guards and they left the room. A few minutes later they returned with a regular looking pony in tow, regular except for the fact that his eyes were green and his face conveyed no emotion whatsoever. Trunks walked over to him and knelt down so that the pair of them were eye level, narrowing his eyes as he let his senses reach out to the pony.
"I've never seen anything like this," he muttered to himself. He reached out with his hand and placed it on the side of the pony's face, who reacted in no way at all. "There's no consciousness, no spark of ki or life...it's like he's nothing more than a robot."
"What did you expect to find?"
Trunks forced his senses to go deeper, digging into the very soul of the being that stood before him. And there, deep within what made that pony him, he found what he had sought. Traces of Sombra's shadow magic, the very energy that flowed through Sombra's veins. And he made sure to never forget how it felt.
"I expected to find this," Trunks said as he opened his eyes and stood up. He then turned to face the other ponies, all who were looking at him expectantly. "I've sampled a tiny bit of the magic that Sombra has used to control this pony. Now all I need to do is fine tune my senses and search for the source of this magical power. And there is where we will find king Sombra."
"Can you do that?" Celestia asked with some amazement.
"Watch me," Trunks replied. He closed his eyes and sent his senses searching across Equestria, searching for the magic and power that matched that which was within the pony. It took him a bit longer than he would have liked, as searching for magic was still a new concept for him, but after a few minutes he felt a source of dark magic that dwarfed all the others. He felt the master that controlled the puppets. He marked the location in his mind before walking to the map, placing his finger dead center on the red X farthest to the south.
"And now we finally have you," Celestia said with a venomous smile. "Today is the day that you will finally answer for all that you've done. Trunks, give me a day to assemble my armies and then we will storm this place so that we can finally put an end to this monster."
"Actually, I was going to ask that you let me do this by myself," Trunks asked, getting Celestia to raise both her eyebrows in shock. "Remember how I said I wasn't going to let any innocent die by evil's hands? Well, I would prefer it if only Sombra died today. And if you bring your army to face him, then there will be plenty dead."
"Are you saying that you believe that you can best Sombra and his entire army without a single loss of life?" Celestia asked, the doubt clear in her tone.
"I do not believe that I can do it. I know that I can do it," Trunks replied with a smile, a smile he hadn't worn since the first time he had faced Frieza. "Let me handle this and by the end of the day your nation will be free once more."
"I have a feeling that you're going to go whether or not I say no, aren't you?" Celestia asked with a smirk. "Very well, brave swordsman. Go and slay this evil monster for the freedom of our land. But if you do need our help, just shoot one of your attacks into the sky and we shall come running."
"I'll remember that. Be back soon."
Without another word Trunks shot into the air, flying through the ceiling and hurling himself in the direction of the dark king. He knew that the ponies saw his actions as cocky and arrogant, but he knew the truth. He wasn't underestimating the dark king in the slightest. Nor did he doubt that Sombra would have all sorts of tricks up his sleeves to try to kill Trunks. But Trunks had faced gods, machines and everything in-between. He had failed and triumphed only to fail again. He knew that there was a risk to what he was doing by going alone.
But he also knew that there were many innocent lives in this world, lives that were being ruined and torn apart by a single evil, an evil akin to that which had torn away his very world from him and all he loved, save one person. And he had sworn on that day he would not allow it to happen again. Not while he drew breath.
So as Trunks sailed over the location of where he had sensed Sombra, he gazed down to find a black fortress made of dark magic that swirled and twisted with menace. He could see hundreds of soldiers down below, who all looked up at him as he came to a stop in the air. He knew that Celestia was right in saying that blowing the whole place to hell with one blast would he the quickest way. But too many would die. Too many would die despite having done nothing wrong. No, they were not the ones that needed to fell Trunks power. Sombra was.
Almost as if he could read Trunks thoughts, the dark king himself walked out onto the tallest tower at the fortress and smiled up at Trunks, motioning for Trunks. Trunks floated down until he was hovering not that far above Sombra, close enough to get a better look at the king. A grey coat, black mane and horn with a red tip. And evil eyes that reminded Trunks of Zamasu. This was him.
"So, you are Celestia's new warrior, who she sends alone to face me," Sombra said with a smile as he looked over Trunks. "i must admit, that while your appearance is indeed out of the ordinary, you are still not-"
Trunks extended his hand and fired a colossal blast of ki into the tower, decimating it and everything in it with one giant blast.