Sentinel Heart ran faster than he ever did running for a Physical Assessment, passing the colorful buildings of ponyville and running far into the clearing by the woods. Castle Twilight was shrouded in a magical energy field but part of it was shattered by the east tower; he panted hard and stopped just short of the barrier, not able to see clearly inside the field but he knew what his gut told him...
"Senior Chief!"
Sentinel turned to see just under a platoon rushing to meet him, a Pegasus and two unicorns among them yet only a few managed to grab their armor and even then none of them had a full uniform, some missing helmets and most missing sandals. It took a little restraint not to start cursing about breaking regulations. Sentinel spotted the Pegasus in armor, the chevrons pointing up and crossed rifles over two rockers just next to the star at the center of his chest plate made him smile.
"Gunny, glad to see you."
The old Pegasus huffed and glared, the marine even had a short halberd under his wing. The other guards lacked weapons but there was only a squads worth of combat oriented personnel stationed at the castle, the commanding officer thought it would be better to keep the defending to leadership while all the guards relied on basic training to fending off attackers. A long time ago Sentinel even though about crossing over to the Marine side of the Royal Guard after the changelings attacked; Shining Armor intercepted his paperwork and talked with him. A lot of yes sirs and no sirs later Shining convinced him to stay a medic, that still doesn't mean he didn't like working with Marines better...
"Whats the situation?"
"Dark magic fired from the east tower it seems, cant tell the exact location but I have a plan already. I need you to fly up and into the field while we stay down here and work on punching another hole to get in."
The gunnery sergeant looked up at the shattered hole in the barrier and snorted impatiently.
"You sure its dark magic? You and I both know what that means and if its true we have to alert the chain."
"I know, and i'll take full responsibility but right now we need to get in there and you're our only flyer."
The Pegasus nodded, taking off from the ground at speeds faster than Sentinel thought the pony could pull off and in seconds he saw his friend fly into a window. Looking back to the rest of the platoon and picking out ranks from those with armor.
"Who's the next highest?"
"I am, Senior. LS1 Keystone."
Sentinel had to force himself not to sigh, the only first-class was a supply support...
"Alright LS1, I need you to go back town and get three other magic users, we cant bust this with brute force and they might need rank to convince them."
"Aye aye."
After the guard was out of sight he turned back to the unicorns, ordering them to start blasting at the shield while the others try and break it around the blast site, anything to try and get past the purple barrier. Sentinel began to worry about gunny in the castle..
Gunnery Sergeant Victorious Assault, life long history of service to the crown and some called him Sun Burnt; a derogatory term for soldiers a bit too obsessed with the job, and the fact that he had an illegal pin up of a rather important white alicorn in his gear locker didn't help his argument...
All his thoughts focused on his duty and he felt his blood pump with excitement, ready for any kind of attack. A loud bash from outside made him nearly stab a bust of Starswirl the bearded but tilted away just shy; huffing at the sound of his friends outside breaking down the barrier. Victorious walked down hallways until he heard crying, gritting his teeth and rushing towards the princes room, just in time to see the princess and her son soaked to the bone, spotted with broken glass and shaking from the cold rain just moments ago.
"Princess!"
Twilight looked up, eyes red from tears and mane a tangled mess, Victorious had to restrain himself from asking just what had happened to her rudely...
"Princess, are you okay?"
The wings fell off of Dusty, the marine looked worried when he saw blood dripping from the princes head; looking back over his shoulder quickly in case the intruder was still around.
"I'm fine, we're both fine."
Victorious watched the alicorns horn light up and he heard the rest of the guard burst into the foyer,spreading out to find an intruder now that the barrier was down. Even if the two wanted to keep what ever happened he needed to know what caused the dark magic..
"Ma'am, we saw Dark Magic tear though your barrier, what happened?"
The marine bit his tongue again; knowing full well what happened. Victorious resisted the urge to glare at the prince, every since day one at Castle Twilight he knew the kid was something dark. Sure enough rumor spread about his connection to King Sombra and now, here was proof.
"It was a mishap, I was working in the library when a surge of magic hit me. What you was was just an attack of greater strength than you're familiar with, not dark magic."
'Horsefethers! You know it was your son that did that, the dark magic in him will only lead to your downfall, allow me to take him to Celestia.' ...Is what the marine wanted to say....Deep down he was cursing up a storm but his face showed none of it; instead he nodded and walked away, stopping the next few guards trying to get in and rounding everypony up to the Combat Operations Room in the west wing. Already thinking up his argument against the prince to present to Sentinel Heart...
_ _
One hour earlier
A knock on the foyer door caught Twilight by surprise, the barrier only allowed herself and Dusty to pass so who couldn't entered yet stopped to knock?
Twilight walked down the stairs and opened the door slowly, peaking around as she opened and spotting a dark blue flowing mane, shimmering like a night full of bright stars and sighing in relief. The door swung open and Princess Luna walked in somberly...
"Princess Luna, I wasn't expecting you today."
"Nor was I expecting to visit today."
Twilight was put off by the dark tone; shutting the door and following closely as Luna walked toward the library.
"What do you mean?"
"....Your son is in danger. You must understand that I have not yet alerted my sister to this for I fear what wrath she might have."
Twilight's heart sank; confusion growing faster than the princess of the night could answer...
"How do you know he's in danger?"
"I saw his dreams last night, I was rushing to his aid hoping they were just nightmares I could dispel but this...this was far more powerful than I could fathom."
They entered the library and Luna shut the door behind Twilight, wanting to make sure the conversation was private. Twilight was looking around the library for a moment, she had to admire her ever growing collection every time she walked in; three stories of shelves upon shelves of books, something to rival the library at the Crystal Empire...
"No doubt you have given the prince his crown?"
Twilight nodded, they both walked in the library slowly, their hooves echoing in the massive hall.
"Then I have troubling news...King Sombra was in his dreams."
"That's impossible, he doesn't even know who Sombra is."
Luna stopped, facing Twilight more serious than she has ever seen the princess; she looked like her sister in a way...
"Something has sparked a memory, or perhaps a ghost or echo, what ever it is...It was tormenting Dusk in his sleep. I will spare you the details, for fear for your well being..."
Twilight sat down, wanting to brace herself on a bookshelf but none close enough to stop her fall. It was all her fault that the crown was allowed to stay; Twilight was berating herself for letting the cursed silver stay in her home. Twilight wished she had some shred of knowledge to comfort her but all that was there was a hoof on the shoulder by the cold princess of the night.
"I know this is hard to accept, but I have good news. The echo was quickly fading, from what I could see, it used all its strength in a failed attempt to reform itself. Tearing at Dusk's mind in blind hope; your son was stronger than I expected, he fought it off until nothing remained."
Twilight looked up, a weight off her shoulders but the fear not quelled. Luna gave a soft smile and helped Twilight up; walking back to the door to the library slowly. Twilight hesitated but followed behind.
"So that's it? What ever it was is gone?"
"I'm not sure, but for now I think he is safe. You should be proud, Princess Twilight."
"I am...but that doesn't mean i'm not scared..."
Luna opened the door, stepping out and thinking of how to best comfort her friend. They stepped into the foyer and stopped, Luna hugged her friend gently, Twilight sighed quietly and took a moment before stepping back.
"Just try and relax, perhaps you should take some time to teach him a few lessons on magic. Take both your busy minds off the subject while I keep my eye out for any more nightmares."
"Thank you...that sounds like an excellent idea..."
_ _
Sentinel Heart stood outside the library, listening in on Twilight's lectures on healing spells and medicine. Felling a little pride when his first attempt to fix the cut on his head was slow going yet what would've taken weeks and possibly stitches from a normal doctor was now just a small scar covered up by silver hair.
"He's good..."
Sentinel took a calming breath, stepping away from the door and into another guard. Almost turning around and jamming a hoof in Victorious Assaults jaw...
"Jeez gunny...sneaking is not a good idea, not now."
"I need to talk to you."
Sentinel remembered hearing those words a lot when he was just a third class, none of those conversations ended well...
"The prince was the one who used dark magic."
Sentinel kept a good poker face, the gunny had his full uniform on now and with the bulk under the armor to back years of training he would intimidate any young solider without needing to say a word. Thats why it was strange when he noticed the dark rings under his eyes and feathers jetting out of place.
"That is a serious accusation, wheres your proof?"
"You know the Princess is covering for him, her explanation was see though!"
"Lower your voice, marine."
The stallion stomped the ground in frustration, glaring at Sentinel with contempt.
"You've heard the rumors as well, the C.O. is hiding it from us but if we had proof to take him, he would open up the file and if the prince follows the same pattern we could lose a lot of guards and perhaps lose the Princess."
Sentinel looked at the ground, thinking hard; he knew that the Commanding Officer was indeed hiding something but that's what the Night guard did, they hid things for a living. Now though he was right on another point; if this goes farther and the gunny was right...He might have to end this writing a lot of 'To The Family Of' letters. Sentinel only wrote six in his lifetime and he swore never to write another.
"I'll talk with Dusty, if I feel like I have solid proof against him, we can contact the C.O. and see where he can take us, deal?"
"...Deal."
Victorious walked away, not bothering to wait until dismissed but Sentinel didn't care, instead he was focused on doing his own research...
_ _
Dusty turned a few books pages, three lay open in front of him and more stack on the desk for later. Twilight had finished her lecture and left Dusty to study on his own and the distraction was perfect. The throbbing headache caused by the glass was gone and he was lost in a world of information, thinking back to how he might impress Sentinel later if he got the chance. The stack of books dwindled one by one and the light in the library slowly lost luster as the candles remained the only light source. Guards wandered in and out every so often to check on him but they never were Sentinel Heart. Dusty yawned and closed the last book, his head jammed full to bursting and body heavy with exhaustion.
"Alright, I so need sleep..."
Dusty dragged himself to his room, noticing most of the guards had returned by now. The door to his room swung open and shut slowly behind him; Sentinel Heart was cleaning up the last of the glass off his balcony and a tarp covered the door. Sentinel looked up at Dusty and stood straight, something about him made Dusty wary...
"Hello...Dusk...I need to talk to you if it's not too much to ask."
Dusty lifted his head curiously, one ear tiled to the side and a little worried about what the guard wanted to talk about.
"Sure..."
"Dusk, I want to ask something very personal. After today's mess I'm sure there's nothing more you want to do but sleep it off but..."
Sentinel hesitated, the look on the colts face somehow inspired guilt.
"I wanted to ask about the...rumors going around about what happened."
"What rumors?"
"...A few guards seem to think that Dark Magic broke the barrier."
The colt tensed, his mother lied for him but he still didn't know if others might have a normal reaction or if Twilight was just special about his talent...
"I...I can trust you with a secret, right?"
Sentinel Heart nodded
"I got my cutie mark today..." Dusty said, giving off a little pride. "And it's in that thing ponies keep calling dark magic."
Sentinel couldn't see under the crusader cape, no doubt a cover for the evidence. Sentinel smiled slightly, no matter what it was it was always a momentous day when you found your calling in life; he was so happy that he got his mark in boot camp that the Drill Sergeant had him running laps for days until they could wipe the smile off his face.
"That's...outstanding, I really hope you become a great prince of your own castle someday with that kind of talent."
Sentinel saw the joy light up the once tired colt, he gave a bow and walked into the doorway.
"Thanks, I'll keep that locked tight and if you ever need help, just call out."
Dusty laughed quietly, watching the door shut and blowing out the candle on his desk once he heard the click of the door. throwing himself in bed and yawning again. Thinking about all he learned and everything he wants to learn about dark magic; no longer caring about whatever stigma was attached to it. Comforting sleep taking him in moments....
_ _
Victorious Assault ducked around a corner when Sentinel walked out, he no longer trusted the stallion to do his job let alone spy for him. Sure enough his thoughts were confirmed when he followed Sentinel and watched him climb into a rack and nod off rather than trying to find him and help protect the Princess. It was luck and a bit of sneaking that he just so happened to hear what the prince said...
"You might have failed, Heart...I'll just have to pick up your slack."