Tide Pool had a hard time sleeping that night. That green flash, those glowing eyes, and that haunting, musical cry. He found himself waking up with a start, in a cold sweat several times that night. Breakfast was met with some light teasing.

"Hey. Stay up too late eyeballing those photots?" His older sister, a light blue pegasus named River Delta teased. "Or did you dream about those big Great White Sharks chasing you?"

"Oh hush. I'm not in the mood." Tide grumbled, sitting down to his bowl of cereal. Ignoring her teasing, he ate in silence.

"Ouch... you don't look too good. Something happen last night lil' Brah?" asked Redwood.

"Uh... After breakfast dad..." Tide said, trying to sound embarrassed.

"Oh! Uh... okay. Sure thing Lil' Brah."

~~~~***~~~~

Breakfast beyond that was uneventful. Tide then took his pa, Redwood, to his bedroom.

"Ok bud... I'm sure your worried, but what your body is doing is perfectly normal." Redwood began, before being interrupted by Tide Pool.

"Dad, I already know about puberty and all that. I know it's happening, and I'm not bothered. What does bother me-" Young Tide stopped to yawn. "Is this." said as he handed the three photos to his pop.

Redwood looked closely at the photographs, squinting, and rotating them. Looking back up at his Earth pony son, he asked "What am I looking at?" Tide didn't respond verbally, and instead pointed out the eyes in the first photo, a short distance away from the dead fish. In the second photo, he carefully outlined with his hoof, the shape of the large aquatic animal grabbing said fish. And in the third, he outlined the tail as it descended.

"I don't know what it is, but when I asked the seaponies, they said it was probably an eel. I've heard all kinds of underwater sounds dad, you know that. You bought the records!" Tide almost yelled, exasperatedly. "But nothing made sounds like that. I think there's something new down there..."

Redwood looked concerned, both for his son, and for what may be in the oceans, right off the coast near his home. Now seeing the shape his son outlined, he began to ponder. Odds are, his son was exaggerating, and it was a simple case of mis-identification. He made this a clear question.

"You sure you didn't just... I don't know, mistake a seal or something?"

"I'm sure dad. I have Pegasus eyes remember? 20/5 in both eyes. I know what I saw, and it was no seal, it wasn't an eel, it wasn't even a seapony playing a prank. No... this is something either new, or so ancient, it's been hiding for ages." Tide declared, staring his red colored father in the eyes.

Redwood looked his son in his eyes. This colt had conviction, and his mind was set. Redwood always was proud of that conviction. His colt always pursued whatever he put his mind to, and to a fault, was relentless in his pursuit; At least, compared to his daughter's lackadaisical mindset. He had personally purchased a fair few of the books on marine biology. The colt however, had purchased even more through his own allowance earnings. If anything, this colt knew most of what he was talking about.

"Alright." Redwood said with a sigh. "we'll go to the library today and see what we can find. Your lucky today is Saturday. If we find something promising... we'll cross that bridge when we get there." He said calmly, ruffling his colt's mane.

Tide smiled. "Thanks dad. I'll be honest, I was half worried I'd have to do this all by myself."

"Worried your family would think your crazy?" Redwood asked playfully. "Now let's get a move on. The Library calls." he declared.

As they descended the stairs of their house, Marina, the green earth pony mare called out, "So where are my two stallions off too?" She asked, nuzzling the young colt.

"Mo~om!" Tide Pool whined, albeit with a small smile.

"We're going to the library. Tide needs information on a report for Miss Bramble." Redwood lied calmly. He hated lying to his wife, but if Tide was right...

"Oh? What are we researching?" She asked playfully.

"Just some Equestrian history. Nothing major." Answered Tide calmly.

"Well alright you two. Don't get in too much trouble!"

~~~~***~~~~

Tide Pool and Redwood both flipped through plenty of books on current marine biology, and even had a small stack on extinct creatures, just in case.

"Harbor seal?" Redwood asked quietly.

"Nah. This thing was green, and much longer than a seal." Tide answered, equally quiet.

Closing the book, Redwood decided to flip through the book of ancient marine biology. He had heard about the ancient fish before; Tide had told him about it some time ago, and had even seen photos of a supposedly extinct whale, only to be rediscovered as little as six months ago. While it was a VERY big longshot, it wasn't impossible. As he skimmed through the book, he'll admit to this day that he learned quite a bit about the marine life in the seas.

Tide however happened to glance over just as his father turned a page, when something jumped out at him. A familiar shaped tail fluke. Fast as a rattlesnake, the little colt slid over and back to the page his father had so casually turned. As he gazed at the illustration, of a giant, multi limbed beast about to bite down on an unsuspecting whale, his mind flashed back to that instant at the blue hole. That brilliant green flash, those glowing eyes, The clawed pectoral fins, and primitive tail fluke... Quietly, he read aloud.

The Leviathan.

Of the many ancient beasts that swam our seas, none were as fearsome as the Leviathan. This ancient monster of the deep roamed our seas over a thousand years ago, and feared nothing. An adult was big enough to bite whales in half. It was reported then to be a blue/green color, allegedly, it had six legs, with the front and middle pairs webbed and clawed, similar to a seals, However the third is speculated to be vestigial; Used for mating, like ancient whales. However, no deceased specimen has ever been recovered, so all we have is sailors reports, and speculation. Sailors from all over the known world at the time often reported that the beasts would glow an iridescent green at night. Some have reported that they heard what would sound like a whale, only much more musical. Ancient whalers would report seeing a bright flash of green light, before a whale would rise to the surface, dead. Almost immediately after, the carcass of the deceased whale would be dragged back down by something massive.

It is speculated that they were bio-electric, similar to electric eels, and would shock their prey to death before consuming them. In rare cases, such as a simple deckhoof, aboard the RES Alicorn, would have seen the beasts take the whale, or whatever was it's current prey. He reported that What he saw was a massive, albeit short, green jaw, with what appeared to be whiskers, like one would see on a catfish; As illustrated.

In some cases, Whaling vessels such as the RES Dusk, RES Trottingham, and most famous, RES Zap Apple, they would mistake Leviathan for whales, and try to harpoon the beasts. The creature would, instead of diving to try and get away, as whales often did, they would turn and attack the ship that harpooned them. Most of the sailors would survive the encounter, but not all would make it. In the case of the Zap Apple... only two of her six life rafts were found, and even then, there were only three survivors per boat. The survivors claimed that the Leviathan displayed almost ponylike intelligence.

Captain Bread Crust of the Zap Apple reported that he held his spear aloft, ready to strike one as it surfaced near his life raft. But the beast never moved, and stared him in the eye. During that moment, Captain Crust realized that if he threw the last harpoon, he would doom his crew; So he lowered the weapon; And in turn, the beast swam away. But not before nudging the small boat in the direction of shore... So the Captain claimed.

This was all before Princesses Celestia & Luna both led a massive culling against the creatures; And have since been hunted to extinction. The only surviving piece of a Leviathan is currently a small set of teeth, on display in the Canterlot museum of Natural History.

Tide Pool couldn't believe it... there was no way it was a Leviathan he saw... but... the pieces fit too perfectly. What he saw was most likely, a young Leviathan.

"What is it, Lil' Brah?" Redwood asked in a hushed whisper. "This it?"

"I'm positive of it... It must have been a baby or adolescent."Tide said, his eyes never leaving the illustration. Before long, the young colt was looking through the card files looking for anything he could on The Leviathan.

~~~~***~~~~

The hours flew by, and before he knew it, he was having lunch at the local hayburger. His saddle bags stuffed full on books and legends about the ancient Leviathan.

"Are you absolutely sure, that this is what you saw?" His rust colored father asked for the sixth time.

"That's six; And yes. I'm sure." Tide answered between bites. "Dad..." He began apprehensively.

"Yeah, Lil' Brah?"

"I want to go back out there. I want to see if I can find it again." The young colt convicted. "I'll understand if you say no, but-"

"Whats the average price for a rental SCUBA rig?" Redwood interrupted. "If your right, I'll double your allowance, I won't make you pay for the rental; And maybe, just maybe, your mother won't kill us. So what's the plan? What do we know?"

Tide was genuinely surprised. He honestly never expected this.

"Well... The Leviathan are said to be bioluminescent. So maybe we wont need a SCUBA rig. Just a boat for a night run. Unless you want to go for a night dive and risk all kinds of sharks or other nocturnal predators. I'm not night certified anyway..." Tide pool responded, suddenly unsure.

~~~~***~~~~

The day went on with no further excitement, other than the two ponies discreetly renting a small boat for later that night, under the guise of 'night fishing'. Dinner as well also past without incident. Just as soon as the meals were finished, Redwood said he was going to take Tide Pool out for some night fishing.

"Night fishing?" Marina asked curiously. "And what's this special occasion? Want to see if he can hook a bull or tiger shark too?"

"Nah. Probably just some perch or something. Something for the dinner table later. Young stallion's going to be a provider for his family someday." Replied her rusty pegasus, much to Tide's minor embarrassment.

"Well be careful. And tomorrow, we're talking about Delta's grades. She's slipping... again..."

"Mo~om! I am not!" River Delta whined loudly.

"Anyway, you two best be off. Bring home something big!"

Tide Pool calmly grabbed his coat off the hangar as he followed his dad out the door. It may be southern Equestria, but the weather was scheduled to start to chill. Nightmare Night was next week after all. The two calmly made their way to the docks, discussing what may happen.

"Okay Tide... I'll be honest. I'm humoring you. I'm almost 95% sure your mis-identifying something else. But... I'm sure this is an extreme longshot, but let's say your right. What are we looking for?" Redwood started.

"Well some confidence is better than none... But we're looking for light. Green light from under the water." Tide replied, then continued. "I can Dive and look around more during the day; But night is easier to see light, and the sailor's reports all say they saw green light. I'm not trying to provoke it to attack, but if... and IF, we see the light... we can go home, and I get to say I was right." He finished as he hopped into their rental boat, and slipped on a life jacket. Redwood followed suit, untying the ropes holding the small skip to the docks.

"Just light huh?" His father replied. "Sounds simple enough. How do you plan on luring it out?" he asked, tapping the red gem that ran the small motor, kicking it to life.

"Well the night fishing was actually a good idea, so why not that?" Tide shrugged, pointing to the blue hole.

The boat the two ponies rented powered through the water to the best of it's ability. It was nothing fancy, just a small fisherpony's boat. Time was slow to the young pony as the boats smaller arcane engine didn't put out the same power as the dive boat, and it felt like it took twice as long as it actually did. Upon reaching the blue hole, The two ponies baited their fishing rods, and began to fish.

~~~~***~~~~

"FISH ON!" Tide yelled as his rod suddenly bent at a very steep angle, almost folding. The reel making a loud whine as the string was being undone.

"Hang tight bud!" Redwood replied, setting his rod down, and helping his son keep a hold of his fishing rod. "C'mon, you know the game. Tire it out!"

"I'm trying dad! GRRRR! This fish is hu-AHHHH!" Tide screamed before he was pulled overboard, into the dark waters.

"TIIIIDE!" Redwood yelled, jumping into the seas after him. Opening his eyes, he watched as his colt released his fishing rod, and began to swim to the surface. Keeping his wings folded, he swam to meet Tide and get them both back in the boat. As they both broke the surface, the fish that pulled Tide under became visible. They found themselves being circled by a large shark. It was to dark to tell what kind, but the side to side motion of the fins suggested this fish was above average for it's size.

"Dad... I'm scared." Tide confessed, holding on to his father's life preserver.

"We're gonna be fine bud. I promise." Redwood said, trying to sound confident, if only for his son's sake. He then noticed Tide's ears twitching, and his Pegasus senses kicking up. Odd... There's no clouds out tonight, so why is his magic telling him lightning is coming? Then he heard it... a high pitched animal call. It sounded... almost musical. Then came a bright green flash, and dull boom, seeming to come from directly beneath them. Redwood's senses told him that lightning had just been discharged underneath him, and... struck the shark...

"Dad..." Tide whispered. "It's right under our hooves!" the poor colt was shivering. Redwood was unsure if it was fear, or the cold making his colt shiver, but he knew he needed to find the boat. Flying was out as an option. Once a pegasus was in the water, they had to swim to shore before they could take off again.

The light reappeared, then slowly moved away from the two ponies, and illuminated the bottom of their boat. Just as the two ponies began to swim towards it, the boat suddenly turned, and began to make it's way towards them. As it got closer, they saw that it was being pulled by the anchor line. As the boat stopped in front of them, Tide was suddenly propelled out of the water and into the boat. Redwood was also pushed back in, but not as much as Tide was. Once they were both in the boat, Redwood turned to hug his son again.

"We're okay Tide. We're okay." Redwood said, trying to use his body temperature to warm his shivering colt back up.

"I-i-t's s-s-t-t-i-ll h-h-here..." Tide shivered. Just as Tide shivered those words, a splash sounded from behind them, and a noticeable weight was suddenly on the back of the boat. Both ponies then turned to face whatever had jumped onto their boat. Two eyes, glowing in the moonlight met their gaze.

Author's Note

Also of note, Please do point out any spelling or gramatical errors.

Also, 20/20 is standard eyesight, 20/10 is better than average, 20/5, while extremely rare in humans, might just be a pegasus standard. Like Rainbow when she was flying. She was able to take in so many details just by passively flying overhead, and casually observing, barely paying any attention to what was happening below her.

I tried to describe the Leviathan as best I could, while also blurring some fine details. Eyeshine and Bio luminescence are both traits of animals that tend to live in very low light to absolute darkness. And no matter how clear the water, or how bright the moon, the light will not illuminate the seas. A night dive is basically jumping in a pitch black pool.