“We could just claim you were under madness effects from the umber hulk?” Twilight offered, frowning at Prominence as she levitated supplies into saddlebags, checking them off a list as she went. "Bandages, canteen, rope, trail mix, glow sticks..."
Prominence paced back and forth nervously. “That doesn’t fix things, though. I’ve been put in the public eye. Somepony, somewhere, is going to start looking into me. They’re going to look for my background. But you know what? Prominence hasn’t existed since before Lu...before Nightmare Moon! Somepony’s going to be asking questions, and we won’t be able to answer. I’m such an idiot, I can’t believe I did this!”
“Relax, relax, none of the reporters know who you are!”
“But the ponies in town do, and any reporter worth their salt is going to to be asking everypony about this. Oh, Heavens above, I need a drink...” All the cabinets in the kitchen flew open as she began scanning for alcohol.
“...No time for drinks, unfortunately...I mean, you can stay here and drink if you really need to, but...The girls and I have work to do.” Twilight said, placing the saddlebags onto her back.
“How are you so calm?” Prominence asked, tears forming in her eyes.
“Oh, I’m not. I’m just trying to compartmentalize. As soon as I finish figuring out why an umber hulk is so close to the surface, and make sure there’s no threat of it resurfacing again… Then I’ll let myself freak out about this.”
“…That’s too dangerous. If your mind is wandering while you’re in a perilous situation...I’ll have to come with you. Otherwise I’ll spend the whole time worrying about you.”
They stared at each other for a long moment, each realizing the other just wanted to do something to take their mind off the present problem.
“So how are you guys gonna leave with all the reporters at the front door?” Spike asked, sipping a glass of water. Twilight and Prominence both stared at him for a moment.
“Fillies and gentlecolts, I have to offer you my most sincere congratulations! You have the rare opportunity to interview the hero of the Crystal Empire himself, Spike, The Brave and Glorious!” Spike announced to the reporters, flexing his tiny arms.
“Go, go! Hurry!”
“Out the back, out the back!”
"Confounded wings! The window’s too small, give me a push!”
Seven ponies stood in downtown Ponyville, surrounded by yellow caution tape. Twilight Sparkle’s horn glowed as she pried open the sealed rift in the ground, and one by one they descended into the darkness. They had to find out why that Umber Hulk had come to the surface if they were to ensure it didn’t happen again, and to do that, they had to see where it came from. As they quietly walked along the tunnels, they prayed that they would not encounter the creature again. Twilight lead the front of the pack, her horn glowing brightly to guide them down the tunnels.
Where Prominence had expected a silent, dreary, deadly serious trek, they simply traveled like a group of friends, taking a walk together, chatting and bantering happily.
“...And we snuck out the back window while Spike distracted them.” Twilight finished.
“So...Why didn’t y’all just teleport?” Applejack asked, confused.
“Shhh!” Rainbow put her hoof over Applejack’s mouth. “Do you hear that?” The sound of distant scurrying filled the tunnel, accompanied by the faint stench of blood. They all braced themselves for combat as they moved forward. The tunnel branched out into dozens of spiraling, dark paths. Eyes peered out at them, then vanished back into their holes.
“What are these creatures?” Rarity asked nervously, her horn beginning to glow in preparation for self-defense.
“Miss Rarity?” A head stuck all the way out of the hole, battered and bandaged. Rarity immediately recognized it as a former captor.
“Oh!...uh...you! Diamond dog!” She chuckled nervously, with no idea what his name was. Dogs began crawling out of the holes and surrounding them, many of them wounded and bandaged, some with broken limbs. “Goodness! You poor things! What happened to you?”
“The diggy bug!” He whimpered. Murmurs of agreement ran throughout the pack.
“The diggy bug?” Applejack asked, raising an eyebrow.
“Did this diggy bug have three eyes and a disco ball?” Pinkie inquired, tilting her head. Receiving confused, hesitant affirmation from the dogs, she rubbed her chin in thought. “Hmm...I wonder if it knows the umber hulk?”
Rainbow slapped herself in the forehead and leveled a glare at Pinkie. Pinkie just playfully stuck her tongue out at Dash.
“Where did the diggy bug come from?” Twilight asked, approaching the diamond dogs.
“Deep, deep down.” The leader replied. “Where the gems stop.”
“And...Why did it come up to the surface?”
They all exchanged nervous glances. Murmurs ran through the crowd, with several of the dogs repeating, “Dig too greedy...Get the diggy bug….”
“Where is it now?” Applejack asked. “Can y’all lead us to it? Maybe we can push it back into the, uh...deep deep down?”
There were gasps of horror and disbelief at the very suggestion that the diggy bug could be contained, let alone the idea of willingly approaching the deep, deep down. Still, the promise of hope, of being rid of the diggy bug for a time, spurred them to hesitant action.
Deep into the tunnels the ponies went, seeking the horrific monster, lead by the two least damaged diamond dogs, who sniffed their way through the branching paths.
“So, uh, what’re your names?” Applejack asked.
“I’m Rex. He’s Buster,” one of the dogs replied, sniffing his way down the path. Every branch seemed like it was either too small for the umber hulk, or didn’t go deep enough underground.
“So, Rex,” Twilight started, staring at the dog, “Why do your tunnels stretch under Ponyville?” There was a small amount of irritation in her voice.
“Diggy Bug dug those tunnels!” Buster quickly stated, before Rex had a chance to answer.
“Oh. I guess that makes sense..." She mumbled, accepting their excuse even though he really sounded like he was lying. "Why don’t any of these tunnels go down?”
“Digging down makes us find diggy bugs!” Rex explained, exasperated. “Diggy bugs hunt diamond dogs, so we don’t dig down.”
“It...hunts you?” Asked Prominence. “That’s horrible!”
The dogs grew very quiet, trembling slightly as they followed the path.
“Oh dear, is something the matter?” Rarity asked.
“We in diggy bug tunnels.” Rex whispered, pointing at the walls.
Rainbow looked at the walls, confused. It looked like dirt, just like every other tunnel they'd been in. “How can you tell?”
“No gems here.” He answered, annoyed at how obvious that should be. “Never were. Never will be.”
“We seem to be staying rather...up.” Rarity pointed out. “How are we going to find the tunnel it first came out of, and force it back in?”
Twilight thought for a long moment. Teleportation would be too risky. “Well, we could ask the diamond dogs, all the diamond dogs, to work together to dig a tunnel straight down that we could push him into?” She offered, turning around and seeing the eyeshine of the whole pack, staying just far enough back to remain shrouded in shadow. Their eyes vanished.
“It’s a big bug, right? Why don’t we just squash it?” Rainbow offered, gaining a horrified shriek from Fluttershy. “I DON’T SQUASH BUGS!” she quickly informed, putting her hooves up in defense.
“Umber hulks are notoriously tough. I’m not sure how much luck we’d have trying to squash it,” Prominence began with a sigh, “Unless we were to use very high powered magic, but in such tight quarters, that could endanger everypony here.” Several of her friends stared at her. “What?”
“Nothin’, nothin’, just...” Applejack rubbed the back of her head. “You’re sure actin’ like yerself.” She smiled.
Prominence nodded knowingly. “This far underground, who would notice that would also care?”
“What kind of high powered magic did you have in mind?” Twilight asked.
“Well, off the top of my head, we could superheat the soil beneath the umber hulk, melting it into lava. That would, unfortunately, kill it. And, due to convection being a thing that exists, we’d all be in very real danger.”
Twilight stared at her wide eyed for a moment, before rushing in and kissing her. “Celestia, you’re a genius!”
“I thought we agreed we weren’t going to do that anymore?” Prominence blushed, looking back at the rest of the group.
“Like you said, this far underground, who’s going to care?” Twilight smiled, before going on to explain her plan.
They had finally found it, and deep underground, in its element, where the pegasi could not fly, the umber hulk was far more dangerous. The ponies ran circles around it to distract it, striking it to keep its attention, doing their best to hold it in place for Twilight and Celestia.
Their horns began to glow. Celestia held ground steady and in place to keep their plan from breaking down the entire tunnel system on top of them. Twilight grabbed the ground beneath the umber hulk, and began vibrating it at incredible speeds. Rumbling filled the tunnels. The dogs covered their ears, whining.
The hard soil beneath the monster began to break down, crumbling away, falling as Twilight created a sinkhole, and Celestia, holding the soil around it, kept the hole from expanding too far. The diamond dogs stared in awe as the dreaded diggy bug was sucked down beneath the dirt.
“There. It should be in a deeper tunnel system now,” Twilight said, panting, “judging by the fact that...well, the fact that it worked. I can’t create a sink hole that doesn’t go to a more open area. There’s got to be space underneath for the dirt to fall into.” She pulled the soil closed over the hole, solidifying it with some enchantments, and then covered her ears as they were overtaken with shouts of joy and celebration. The ponies were all picked up and whisked away by cheering diamond dogs.
“We take you to big feast!” The pack leader, Rover, said.
“You’re not going to eat us, are you?” Pinkie asked, suspicious.
“No, no, dogs don’t eat ponies. Dogs just eat pigs, and birds, and bunnies!”
Fluttershy fainted.