Twilight leaned against Applejack. Fluttershy dragged her wings behind Rarity as Pinkie Pie led them out of the clearing and down the path. While still dark and frightening, the forest no longer seemed to be trying to eat them. Lit blue and green florescent, from what Twilight didn't know, the forest felt pleasantly indifferent to their presence. Twilight guessed it was because they were on the well-trodden path to the ancient castle of the Knights of Economics.

It had been an hour since Rainbow Dash had flown off on her own. Twilight was worried, but the other ponies seemed less concerned about their friend alone in a malevolent forest full of dangerous magical creatures and more about their flagging stamina.

“My hoofs ache,” Rarity whined.

“My wings ache,” Fluttershy sighed.

Twilight turned her neck. “Then get them off the ground!”

“My side aches,” Applejack complained.

“Then you shouldn’t have kicked me!”

“My Pinkie Sense aches,” Pinkie Pie said. “It feels really knurly.”

Twilight frowned. “A small protuberance?”

“Exactly! It’s like sitting on a ridge for a really long time but in my knapp instead of my rump.”

The stabbing pain in her ribs sucked Twilight’s patience away. “Aren’t any of you worried about Rainbow Dash? She could be—who knows what could have happened to her?”

“Rainbow Dash is faster than a rattlesnake in July,” Applejack said. “Nightmare Moon would have to get up pretty early in the morning to catch her.”

“There won’t be a morning if we don’t defeat Nightmare Moon!”

“No need to shout, sugar cube. I’m right here.”

“I shouldn’t have trusted that parasprite,” Fluttershy moaned. “I’m so sorry.”

“We were all taken in,” Twilight said.

“Except Rarity,” Applejack pointed out. “When she turned to Pinkie, whispered something and giggled, the parasprites shut up like their own granny had snapped a stick at them.”

Pinkie stopped. She tilted her head. “I sense water. A lot of it.”

“With your Pinkie Sense?” Twilight asked.

“No, with my ears, silly.”

They came to another clearing, much larger than before, one where the space extended all the way to the sky. The ponies blinked in the sunlight and squinted their eyes at a castle and the wide moat that surrounded it. There was the distant sound of rushing water. Twilight wondered where it came from.

The castle was tall and mostly grey, though Twilight thought she could make out what might have been chipped and faded paint on the distant stone. Conical spires topped the towers, and in the back of the bailey some kind of keep or library loomed. The drawbridge was raised.

“Rainbow Dash could fly us across if she was here,” Applejack said.

The water exploded like a latent tsunami. Twilight reared back at the unexpected torrent of rain.

“NOT MORE PONIES! GO AWAY!”

The scream was like the explosion of a volcano that spat fury instead of lava and gas, and it came from the mouth of a giant sea serpent.

Covered in glittering, damaged purple scales that looked like they had been dragged through a minefield of explosive soap, the serpent rose to a frightening height and roared. Its head was covered in odd tufts of orange hair, and it wore a fabulous mustache with utter panache.

Twilight and the others wilted at the sight and sound of an angry sea serpent, except for Fluttershy, who stepped forward.

“Wow!” she gushed. “A real sea serpent! What happened to you scales?”

“A flying pony happened,” the serpent snarled. It raised a hand tipped with four razor-sharp claws and brought it down. Twilight teleported so close to Fluttershy that they touched and teleported again before the claws closed around the space they had just occupied.

Her heart pumping, adrenaline drowning the pain in her ribs, Twilight left Fluttershy by the trees and teleported back to the other ponies, who wisely turned and fled for the forest.

The serpent’s tail whipped out of the moat with a huge burst of water and blocked their path. Rarity screamed.

Like the rest of the serpent’s body, the scales on its long, thick tail were damaged and cracked. Twilight wanted the serpent’s attention on her, so she fired a magical blast from her horn into one of the gaps.

The serpent roared, nearly knocking her off her feet. Then it attacked.

The serpent slammed its hand down flat like it intended to crush her. Twilight teleported onto the back of the hand. Its long arm stretched out invitingly, so she ran up it, sinking her hooves into the gaps among the scales. The serpent roared in pain and tried to shake it off, but it’s hard to unbalance a teleporting pony who isn’t relying on her hoofs to stay upright.

Besides, she wanted its attention on her, and teleporting made a good show. Fluttershy couldn’t carry them across, and it took too much time to charge the magic necessary for such a far teleportation if the serpent was attacking them. As long as the bridge was up and the serpent wasn’t down, they couldn’t get to the castle.

Had Rainbow Dash made it to the serpent? What had happened to her?

The serpent’s other claw reached for her; she teleported onto it instead and kept running. She teleported up the arm and into the air, biting onto the long hair of its mustache just in time. Again she vanished in a lavender flash, appearing on the top of the serpent’s snout. Her horn glowed with magical power.

She couldn’t win a fight with a sea serpent. But maybe she could force an injured and desperate animal to submit.

Twilight fired. The serpent screamed. So close to the serpent’s mouth, Twilight’s whole body shook with the incredible noise.

“S-s-stop fighting us,” Twilight chattered, “or I’ll blast you again!”

The serpent’s voice sounded distorted and odd from the top of its snout. “Instead of threatening me, little pony, you should be begging for the lives of your friends.”

Twilight looked over the edge of the serpent’s snout. Its tail coiled around Pinkie Pie, Rarity and Applejack, who bucked and struggled but to no avail.

It could crush them instantly. There was no way she could reach them in time.

“You’re so close to my mouth,” the serpent said. “Use your magic trick to get inside and I won’t hurt your little friends. It has been so long since I’ve tasted pony flesh.”

So it hadn’t eaten Rainbow Dash. Where was she?

“You promise not to hurt the other ponies?”

“Twilight, don’t worry about us!” Applejack shouted. “You gotta stop Nightmare Moon!”

“Worry about us!” Rarity shrieked. “Worry about us!”

“Before I teleport into your mouth,” Twilight said, “did you see a rainbow-haired Pegasus fly by?”

The serpent snarled. “So you’re friends with it. Where is it hiding?”

“Right here!”

A rainbow streaked across the sky like a hippie lightning bolt. Before Twilight could even begin to shout her relief a pair of hoofs gathered her up and sped toward the ground. The skin on Twilight’s face stretched back as the earth approached at an incomprehensible yet clearly unhealthy rate.

“Teleport!” Rainbow Dash said.

“Huh?”

“Teleport!”

Twilight realized her hoofs were touching three different flanks. She concentrated her magic and teleported.

The five ponies reappeared fifteen feet away, gasping and elated.

“You sa-a-aved u-u-us!” Rarity wailed, clutching Rainbow Dash tight.

Rainbow Dash pushed her away. “Get off, you’ll slow me down!”

“Knew you’d come back,” Applejack said.

“Sometimes a pony just needs to fly,” Rainbow Dash said.

“Rainbow Dash!” Fluttershy appeared out of the safety of the trees, galloping toward them. “Are you all right?”

Twilight stepped in front of the others, lavender glow surrounding her horn. “Let’s not celebrate yet. We still have a serpent to beat.”

“I can get us all past the monster and to the other side,” Rainbow Dash said, “but I need you to teleport inside and open the gate so we can get into the castle. I can’t protect ponies on both sides.”

“Got it. Take me first.”

Rainbow Dash wrapped her legs around Twilight’s belly. As the serpent glared at them, heaving with anger, Twilight regretted all the fruit pies and chocolate pastries she had ever eaten.

The serpent’s hands slammed on the bank, rocking the ground. “Hold still, you miserable ponies!”

“Ready?” Rainbow Dash asked. Twilight could hear the grin.

"Not exactly—"

Twilight realized Rainbow Dash had taken off when her brain observed that her eyes were about to explode. The scream had died in her throat thirty feet back and a quarter of a second ago. Rainbow Dash dodged and swerved around the serpent’s swiping hands and deposited her on the other side. Twilight nearly wept for the feeling of solid, unmoving ground as Rainbow Dash saluted and, well, dashed off to the other side.

Twilight had her own job. She teleported through the wall and into the castle.

The interior was dusty and bare. Rats scurried along the floor and spiders took to the walls. Clearly no pony had lived in here for a while.

She spied the windlass. Taking hold of it with her magic, she cranked the mechanism as fast as she could. The bridge complained like Spike in the morning, but like Spike in the morning a liberal application of magic got it moving.

With a terrified squeak Fluttershy ducked under the grill and scampered into the gatehouse.

Twilight gestured to the windlass. “Keep cranking it!”

Twilight didn’t wait for Fluttershy’s breathless assent as she ran outside, but it was clear Rainbow Dash didn’t need her help. She dodged around the serpent like it was moving in slow motion, and maybe to her it was. She spun and twisted, pulled off death-daring dives, and if the situation hadn’t been urgent Twilight would have thought Rainbow Dash was showing off. Twilight was prepared to teleport or fire a beam, but Rainbow Dash had the serpent’s attention entirely on her and was handling it masterfully.

She deposited Applejack, who looked relieved to set her hoofs on the dirt, and Pinkie Pie, who hopped inside, and finally Rarity, who only stopped screaming to breathe so she could start screaming again. Twilight suspected Rainbow Dash had deliberately saved her for last.

With the four safely inside, Twilight called Rainbow Dash to her and regretted it immediately as she was lifted into the sky. The serpent faced them and bellowed, swiping its terrible claws. Twilight teleported. They appeared a few feet away from the serpent’s large eyes, which widened at the sight of Twilight’s pointy horn glowing with magic so near the vulnerable organ.

“Let us be,” Twilight said, “or face the consequences.”

They began to fall. “Twilight!” Rainbow Dash grunted. “You weight almost as much as Pinkie Pie! I can’t carry you for that long!”

Twilight teleported them up again. She wasn’t finished. “And when we come out after defeating Nightmare Moon, you’re not going to bother us.”

The serpent blinked. “Excuse me, but do you mean to say that you are not allied with that terrible Alicorn?” Next Chapter: Fluttershy's Test: Expected Utility Estimated time remaining: 49 Minutes