Twilight and Blueblood were mostly silent as they followed the tunnel he had pointed out would take them directly into the throne room. Rarity was still out cold on the prince's back, an arrangement he would have whined about if the day hadn't been worse already. They simply walked, not even making eye contact with the other. Twilight decided to end it. Taking a deep breath, she asked,

"So...you really know these secret tunnels well?"
"Hm? Oh yes, I suppose I do. All the time I've lived here, I'd be disappointed if I didn't." Blueblood responded.

"Well, I've never heard of them before." Twilight said, huffing. This got a scoff out of the prince.
"Come now, Twilight. Surely you have some degree of curiosity. Why, I first found this tunnel when I was just a colt, playing on Auntie's throne."

The image conveyed brought a grin to Twilight's face as he continued.
"Yes, I recall her being out for the day and her guards mysteriously absent. I thought it a marvelous idea to explore the seat of power in our country. Never knew I'd figure out where all those guards had been lazing about. I even remember the time me and Cad-Oh, what is this doing here?"

The tunnel they were came to an end at a circular cut into the wall. Inside it was a stone platform imbedded in the ground. There was a switch to activate the device, and leaning underneath it was a sword held in a very ornate sheath. Pulling Rarity off his back and transferring her to Twilight's, he rushed over to the weapon and held it aloft. The handle had a single blue gem at its tip, its wrist guard of carefully crated silver. Removing it from its black casing encrusted with gold, Twilight could see the blade shimmering even in the low light of the tunnel. Blueblood gave it a few experimental swings, each of excellent form, before resheathing it and hanging it over his shoulder by the sash.

"This should be in my room! Who on earth had the nerve to put it down here? Does no one have any respect for other's property?! Why I-"

Rolling her eyes at his indignant rant, Twilight herded him onto the stone platform, flipping the switch inside. The stone beneath them rumbled, then began to gently ascend into the chamber's top. She peered upwards, and could see on it's ceiling a square slab of stone cut from the rest of it. As the platform slowed to a stop just above it, Twilight's horn lit up as she used her magic to push it. It gave way easily, and with a little difficulty carrying another pony, she climbed out of the underground at last. The prince followed her as his little tirade concluded.

"-and throw him or her right back into the dungeon! Oh, good, she's not here."

One look around her was enough to answer who 'she' and where 'here' was.

"This tunnel leads directly in front of Celestia's throne!?" she inquired loudly. Blocking the entrance behind them, the prince tried to shush her.

"Shhhh! Yes, yes it does. Keep it down, do you want everyone in Canterlot to hear you? Or Auntie herself?" he hissed.

Twilight winced before shaking her head. "Oh nononono, she can't know about this! Or any of what's happening!" she panicked, jostling the mare on her back. Now it was Blueblood's turn to roll his eyes.

"Twilight, please. She's not going to find out about this." he said as he approached the doors leading out of the room. "She's the kind of mare that won't recognize something like this until the reality of the situation smacks her right in the-"
Bam!

The door opened before he could touch it, hitting him square in the face. In the doorway stood a white unicorn stallion clad in purple with a very determined look on his face, which melted as he saw his little sister.

"Twily! Thank goodness! I've been hearing some real bogus rumors about you and-"

At that moment, the door creaked away, revealing the pony in question. He rubbed at his bruised muzzle, but upon seeing who caused it, he tried to creep slowly out of the room. He was spotted quickly.

"Blueblood! Ol' buddy, ol' pal,.....We need to talk. said Shining Armor, his voice giving way to a tone that suggested nothing but ill tidings. Nevertheless, he put on the fakest smile he could muster and followed Shining as he headed outside towards the courtyard. He shot a pleading look to Twilight as he did so. Thinking quickly, she carefully put Rarity down in the closest chair she could find and ran up to her brother's side.

"Wait, Shining! I swear, me and him aren't-"
"Twily, please!" he interrupted. "This is just between me and B. Just stay out if it." His sister looked hurt, but she stood back anyway.

As they entered the field turned orange by the setting sun, Twilight stood back on the stairs, watching them. Her brother faced the prince with a stern look, who himself was beginning to falter.

"Now, B. I know you think you're a big hit with the mares."
Compared to you, anyway, but go on. The prince thought.

"And I know you might feel compelled to talk a big game about your success with the ladies." he continued in a manner that suggested the words he inflected were less than believed.

"But I have to ask you to please, for all our sakes, keep my little sister out of it?"

Blueblood raised an eyebrow. "Keep her out of it?" he repeated.

"Yes, dude." The other unicorn urged. "I mean, you've got the whole city worked up over it! You even fooled Cadance into thinking you two have something! Just, don't go saying things about my sister, alright?" he said, beginning to turn away.

"Hold it right there, Armor." the prince said dangerously. "What makes you so sure I'm spreading rumors? And what makes you think they're just rumors?"

Shining turned back to him, holding a good-natured smile, but with a hint of anger evident.

"Because, I know you, and I know my sister, and I'm pretty certain that nothing you do to her would be worth bragging about."

Blueblood got a furious look about him, and looked around. Twilight was still watching, quite unaware of how the situation was progressing, but he also noticed that a steady stream of royal guards were congregating on the sidelines, spectating them as well. He gave a strong huff, and put on the grin that was the bane of those who knew him and those that thought they did.

"Well, I think Twilight would disagree with you."
"Why's that?" Shining asked, rage gradually building on his face.

"Because, Armor. Just over a week ago, Miss Sparkle made some quite similar assumptions. Do you know what happened a week later?"
"I don't know, B. What?"
"Me. Her. My bed! Face down! Ass up! Moaning my name!"

Every other pony listening in either gasped, or turned to Twilight, whose entire face was reddened by the outburst.

In a split second, Blueblood found himself on his back, his forehooves pinned, his sword removed, and Shining Armor punching him in the face. Each blow came down harshly, his face was pushed in a new direction every time, and the only thing he could hear above the sheer force behind them was Shining growling threats between thrusts.

"Don't!-you ever!-touch!-my!-sister!-again!"

His vision was obscured by the hoof hitting him, but Blueblood could still see the guards watching them. Just watching them. Not rushing to help, not raising any fuss, not even cheering for their captain. Just watching. With only the occasional mocking cringe.

Once again, Blueblood thought, even under the assault, Canterlot's wondrous and formidable Royal Guard prove utterly useless. Because they're idiots. Worthless idiots!

A toothy scowl crossed his face as he slowly rose up, the punches beginning to make him flinch less.

And they're idiots because they're picked, chosen, and trained by this bone-headed simpleton! He brought his forehooves in front of him, blocking Shining's next blow. To his brief surprise, there was a bright, purple energy field surrounding them. And I'll be damned if I let this lowborn moron get the better of me!

Shoving Shining's hoof aside, Blueblood swung it back, catching him in the jaw, then swinging it back and hitting him again. With a savage yell, he thrust them forward, hitting Shining in the chest and shoving him off. He tried to quickly jump to his feet, made difficult due to still being restrained by Shining's magic. the unicorn himself had recovered quickly from his counterattack and charged at him again. Ready for him, Blueblood raised the bright bubble over his head. Shining stopped in front of him, confused. Blueblood then brought his hooves down on his head savagely. The shield shattered with a sound like glass, and the bits flew away into nothingness.

This didn't halt Shining for long, however. he brought his head back up, barely missing the prince's, then through several punches to the prince's front. Undeterred, Blueblood rammed his shoulder in to the other stallion before following up with strikes of his own. They traded blow after blow, a punch there, a kick here, even abandoning hooves entirely to butt their heads together, like dueling rams.

Twilight saw every bit, and was shocked to witness it. She had never seen her brother fight so savagely, and had thought the prince without a violent bone in his body. She had always pegged him the cowardly type. So wrapped in the bewilderment and subsequent concern, she had yet to notice that the fight hadn't been broken up by the assembled guards. But when she did notice, she reacted immediately.

"WHY AREN'T ANY OF YOU STOPPING THEM!?" she bellowed. The guards present looked at her and back to the fight uneasily.
"I have requested they not intervene, Twilight." said a voice behind her. Whipping around, she came face-to-face with the Princess of the Night, Luna.

"But, but why!? she begged, "They're gonna kill each other!"
"I assure thee that I will step in if either of them are in real danger. But this fight must happen, Twilight. It will do both of them well to work out their aggressions now. Surely, you wouldn't want them doing this at, say, your wedding?"

Twilight's face dropped.

"Yes," Luna responded to her expression. "I am well aware that you have become quite taken with my grandson and I must say, I heartily approve of your courtship. And don't worry, I have yet to tell my sister of this news."

Twilight let go of a breath she had no idea she'd been holding. Luna chuckled and watched the fight with her. Blueblood had gotten the upper hand and was shoving Shining's face into the dirt, laughing heartily in triumph.

"Interestingly, I had planned long ago for such fights to be traditional in Equestria. I feel it gets rid of tension between friends and family quite easily. Pity my own stallion hadn't gotten his chance to partake. My sister would jump at the chance to face him. Not to mention I've found mares of this day and age can quite get quite....stimulated by the activity." she said, looking at Twilight knowingly. Twilight didn't understand until she felt the throbbing sensation at her back again. Blushing madly, she turned back to the fight.

Shining was back on top again, this time sitting on Blueblood's back, and pulling one of his back hooves backwards. Blueblood was clearly in pain, his face twisted and his front hooves scrambling for a foothold. All of a sudden, he touched something glinting in the grass, upon seeing it, his face lit up, and he sneered at the unicorn atop him. His horn began to glow, and from out of the grass came his sword, still covered by it's sheath. He brought the butt of it to the back of Shining's head, and when he turned around, he swung the weapon at him, getting him in the mouth hard enough for the prince to buck and dislodge him.

Blueblood got back on his hooves, his sword floating in his telekinetic grip, and a manic, but somehow elated look on his face. Slowly, he withdrew the sword from it's covering, and tossed the beautiful sheath onto the ground. His blade shined in the sunset's light, and he charged to engage the Captain of the Guard. He gave it a mighty swing for his head, only to find it blocked. Shining projected a single plate of magic to protect him. Pulling back, Blueblood swung again, only to be blocked once more. Again and again, Blueblood made as many thrusts, slashes, and stabs as he was able, only for each and every one to be blocked with Shining's magic. Finally, on one particular strong jab, Blueblood tugged at his sword, but this time, it would not budge. It cut through the barrier Shining had made, but was tightly gripping the blade. The unicorn smiled, and his eyes shut as the shield sputtered, then burst. The force of the magic sent the prince flying backwards.

He landed a short distance away, with his sword beside him. At first, he slumped, unmoving. Then he slowly rose to his hooves, and his sword rose with him. The sword began to shake, his magic beginning to glow brighter on it. He reared his head back, then swung it forward. His sword followed his movements, at the end being released and spinning, seemingly on its own volition, towards Shining. Thinking quickly, Shining erected a shield in front of him, ready to catch the sword. It struck his protection, but it did not stop moving, and simply kept spinning, striking the shield over and over, creating a sort of vile grinding noise and a shower of sparks.

Shining Armor concentrated on keeping the weapon at bay, but out of the corner of his eye, could see Blueblood, strolling over to him. When he was in full view, he could see he had inexplicably calmed down, and held a quite serene and controlled visage. While his eyes darted between him and the sword, Blueblood simply watched him struggle with mild interest. Sneering, he set his horn aglow. The sword sped up considerably, the sparks flying faster and the grinding of magic on magic deafening.

Shining began to sweat from the strain, when he could see his shield begin to crack. Fearfully, he decided to dive away from danger, abandoning his shield and letting it be destroyed. The sword struck the ground and stopped abruptly. Unfortunately for Shining Armor, the direction he had chosen to dive in led directly into the prince's outstretched hoof. He fell to the ground, panting, his energy spent. Blueblood walked over to him, pulling his sword out of the ground, and held it over him. He got a glare from the captain, full of venom. But the prince knew it was over. Turning, he walked back towards Twilight, who was on the edge of her seat, wings fully extended, and mouth agape in amazement. Luna was there as well, smiling softly at the clear winner of the fight. Blueblood began to smile back, but felt a sharp pain at the back of his head. He turned to see Shining, standing but weak, and levitating a trio of stones.

Blueblood dropped his sword. He stared at the defiant unicorn some yards away. He began to breath deeper, and more harshly. His eyes burned. The look he had on his face was now one of monstrous brutality. Shining dropped his stones and looked at him with fear. His eyes...they were changing. Their normally light blue areas were beginning to glow green, and a thin, purple mist was coming from their corners. Shining recalled in one minute, a great, black cloud in the north, that had come close to extinguishing him. In the next, he feared for his life again.

Blueblood starting advancing quickly, the same harrowing look about him. Shining casted a full body protection spell. the dome spread out before him just as Blueblood broke into a charge, lowering his horn. Seeing the barrier, his horn flashed, and Shining suddenly felt a great, horrible squeezing sensation on his mind. He clutched his head in pain, but stopped when he noticed something crucial. His shield was gone.

"BRAAAAAAAAAAAUUUUUUUGGGGGHHHHHH!" Blueblood gave a great, unponylike roar as he as was upon his opponent. Shining could only brace himself as he was jabbed by Blueblood's horn. At first, he believe he had been stabbed, but looked down to see it was only hooked into his armor. It was hardly much relief, as Blueblood reared up, hoisting him into the air. He gave him an evil, teeth-filled smile. Which Shining could only return weakly.

Then, with a sound that was halfway between a fog horn and a muffled cannon blast, Blueblood shot Shining Armor off his horn with a burst of magic. The captain sailed high into the sky with a yell that became more and more distant till he was nothing but a twinkle in the sky.

Blueblood fell back to his hooves, and the dark energy faded from his eyes. His breathing was labored. He simply stared ahead, coming down from the adrenaline rush he had just expunged.

The two princesses now both had look of boundless surprise. Luna was the first to recover.

"Well. That was quite exciting." she kicked off from the stairs and walked to her grandson, with Twilight following in shocked silence. They moved in front of him, with his eyes darting in their direction the only means of knowing he registered them. "Prince Blueblood!" Luna spoke loudly, "You have proven yourself quite formidable! I declare you the winner of this stud match and hereby allow you to claim your mare as you see fit!"

"Claim his what?" Twilight asked. Luna didn't answer, but simply used a hoof to shove Twilight in Blueblood's direction. She was stopped when she bumped into his broad chest. His broad, dirty, muscular, sweaty chest. she caught herself thinking as she gazed into his own surprised eyes. The guy who just....beat my big brother. She closed her eyes and pursed her lips, giving in to the strange feeling that had grown in her since the fight started.

Blueblood just stared at her. Then held her closer as he moved towards her waiting mouth.

Author's Note

Originally, the prince called Shining 'Wrath Sponge' before charging.
I figured berserk screaming worked better.

And you tell me B wouldn't have this in his repertoire.