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Chapter Text

Rexy yawned as she woke up to the scent of the fresh morning jungle air. Turning her huge head slightly to the right, she saw that her colossal mate (whose head alone was over twice her size!) was still asleep. Gushing with fondness and affection, she nuzzled him tenderly along his huge snout. 

Big Daddy stirred, opening his eyes blearily. He turned to face his mate of six months, and gently nuzzled her. Rexy moaned low in her throat as she reciprocated his nuzzles with her own, her own jaws positively tiny compared to his. She shifted her 10-ton body and leaned fully against his colossal, 18-ton frame, rumbling as she pressed against him as much as she could, wanting all of his warmth, his scent…all of him. 

Big Daddy rumbled deeply as he lightly pushed against her, nuzzling her with painstaking gentleness and tenderness. As petite as his mate was compared to him, she was still strong, brave, and a persistent fighter through and through. He was very glad and proud to have a small but strong mate like her. 

Big Daddy huffed, amused and touched at how clingy and thirsty his mate was. He supposed, after her life-threatening encounters with the Indominus Rex and the Giganotosaurus, that she would be especially attached to a male Rex who was large and powerful enough to easily obliterate either of them - or even both of them together. 

The two of them cuddled there until the morning sun rose even higher above, its rays spilling through the canopy of the towering redwood trees. Big Daddy rose slowly to his feet, followed by Rexy. Sniffing in the fresh and sweet jungle air, Big Daddy raised his head and opened his mouth in a deafening, terrifying roar that travelled miles and miles in every direction. 

Rexy joyously opened her mouth to join in with her, ironically, much deeper but softer roar; the two roars, like a pair of massive eagles, soaring through the air until the surrounding mountains echoed with their wingbeats. Big Daddy and Rexy waited, before several pairs of deep roars one after another indicated the presence of Buck and Doe, Hank and Big Eatie, Junior and Little Eatie as well as a final, especially deep and thunderous roar indicating Magnus’s presence. 

Satisfied that none of their family were missing, Big Daddy and Rexy took long, thunderous strides forward, ready to begin their daily territorial patrols.

Character List

Big Daddy: OG Primal Carnage Tyrannosaurus Rex - 18 tons

Magnus: Magnatyrannus - 17 tons

Rexy - 10 tons

Buck - 10 tons

Doe - 9 tons

Junior - 10 tons

Big Eatie - 9 tons

Little Eatie - 9 tons 

Hank: Prehistoric Planet Male Tyrannosaurus - 11 tons

Chapter Text

“I want you to train me, Junior.” Little Eatie said.

“What?!” Junior looked at his mate in shock, she had never expressed any interest in learning combat. “Why all of a sudden…?”

“Because I don’t want to be a burden to you.” 

Junior stared at Little Eatie. “Liz, we’ve been through this before, you’re not a burden…” 

“I AM!” Little Eatie roared at him. “When we were attacked by that Indominus, I wasn’t any help at all…if Uncle Magnus hadn’t arrived in the right moment…”

“Oh, Liz.” Junior went forward and embraced her, intertwining his neck with hers. 

“Y-y-you could’ve died, Junior! I nearly lost you, just like I nearly lost Mom to that Spino! I’m sick of feeling weak and hopeless. I want to be able to lend a hand! I want to be able to fight back effectively against our killers and oppressors!” She leaned against his embrace, relishing the familiar warmth and security of her mate. 

“Alright. I’ll teach you.”

Everyday, Junior and Little Eatie sparred. Everyday, Little Eatie was easily beaten in the first week or so. But gradually, she began to improve. She was over a ton lighter than her mate, so while she was much weaker physically, she had speed and agility on her side. 

Junior had also gotten Hank, Big Eatie, Buck and Doe in on the training as well, and they sparred with Little Eatie from time to time. Eventually, four weeks after Little Eatie’s training started…

Little Eatie panted as she planted her foot over Junior triumphantly. 

“Alright, alright, you win.” Junior said, his pride slightly wounded at having lost to a smaller and lighter female. 

“Yes! Now I’ll be able to hold my own against a Spino or Giga just like you.” Little Eatie gave a triumphant roar of victory. 

“Awwww, don’t be sad, sweetie.” She said as she helped her disgruntled mate to her feet. 

“Sigh, alright. The fact that you won means I succeeded at teaching you anyway.” Junior growled. 

“What?” He looked at her in puzzlement, she was staring at him intensely. 

Before he knew it, she launched herself at him and began nuzzling him tenderly. 

“My strong and handsome teacher…deserves a reward, don’t you think?”

Chapter Text

Hank clamped his jaws down the right leg of the 10-ton bull Columbian mammoth and bit down, eliciting a trumpeting scream of agony from the pachyderm as its leg was entirely bitten off from the knee down. The mammoth toppled over onto its right, and Hank swerved quickly to avoid being crushed. 

As the mammoth came crashing down, Hank latched his maw around its neck and shattered it with a sickening crack. 

He sent a spine-chilling, low frequency rumble through the forest before digging in, biting through the thick skin with no difficulty and devouring huge chunks of flesh. His new mate, Big Eatie, appeared from the forest. 

With a grateful purring rumble, she began to dig into the carcass hungrily. Ever since the land had been purged of their competitors, and ever since she had mated with Hank, she had bulked up; now pushing 10 tons in weight. 

The bones of the Columbian mammoth cracked and exploded under the bites of the two mated tyrannosaurs. Both Hank and Big Eatie growled and rumbled in contentment as they hungrily consumed the marrow-rich bones. Hank picked up a particularly large rib bone in his maw, and instead of consuming it, turned to Big Eatie. With well-practiced ease, Big Eatie grabbed hold of the other end - their lips just less than an inch from each other -  and the two tyrants pulled back in sync, tearing the massive rib bone in two halves. 

Chapter Text

Big Daddy #02 and Rexy #03

THUD. THUD. 

The Indominus Rex looked up in surprise just as she was about to finish Rexy off. 

A colossal, robust Tyrannosaurus Rex with glaring red skin and a set of heavy armored osteoderms running down its back was staring right at it, hatred burning in its eyes and radiating killing intent on a level that actually sent shivers of fear through the Indominus. 

She lifted her claws from Rexy and stepped over her to meet the new challenger with a deafening, shrieking roar. The Red T-Rex also answered with a roar of his own, a terrifying scream from another world. 

Without further hesitation, the Rex charged, and the Indominus charged forward to meet him, ready to slash him with her claws. 

But this was exactly what the 12.5 ton T-Rex had been waiting for. 

Rexy had gotten steadily to her feet and shook her head to clear her dizziness, before the sound of an unholy, pained shriek from the I-Rex caused her to look over. Where the White One's right clawed arm had been, there was now only a copiously bleeding, pitiful stump. The White One was screaming in agony while the huge Red One in front of her - she recognized him as one of her kind - was actually devouring it in front of her. 

The Red One...she had never seen a male in her life before. And while his head was unusually huge, she couldn't help but stare at him. A robust and massive body full of well-defined muscle - he was definitely far stronger and larger than she was. 

She wanted to join him in demolishing the hateful White One, but a part of her understood that she didn't need to. She watched as Big Daddy expertly dodged the Indominus's vengeful lunge, before swerving to the side with surprisingly agility and mobility, and latched his gargantuan maw around her neck in a deadly chokehold. 

Normally, Big Daddy would just instakill her like he did to the Spinosaurus. But he saw how the White One had brutalized the Brown Female, and thus he wanted to make her death as slow and painful as possible. And by the sounds of the pitiful, terrified, choking gurgles she was making as he ever-so-slowly increased the hydraulic pressure of his jaws, he was definitely succeeding. 

CRACK. 

Big Daddy held up the severed, decapitated head of the Indominus Rex in his jaws, before tossing it aside contemptuously, and let out a triumphant roar. 

Rexy watched with wide eyes as he roared triumphantly. Part of her wanted to flee; she didn't know how the Red One would respond to her. 

Big Daddy saw, to his relief, that the Brown One had recovered. She tensed as he took a few, cautious steps over, before letting out a low, soothing rumble to assure her that he meant no harm. Rexy let out a puff of relief; she didn't want to fight him. 

Driven by curiosity, she moved forward to take a closer look at him. She was intelligent, and she did feel gratitude to him for saving her. She also did find him strangely attractive. 

Big Daddy noticed her interest in him, and he would be lying if he said that he didn't feel any attraction towards her. The two Rexes put their snouts close to each other, less than an inch apart. They sniffed each other, familiarizing themselves with the scents of each other. 

Big Daddy turned, before looking back and motioning for Rexy to follow him with a sideways nod of his skull. He knew a place where she would never have to starve again. Rexy followed, the two Rexes leaving the scene...and leaving a very confused and shaken group of people (with a raptor) behind. 

Big Daddy #03 and Rexy #05

For the second time in her life, Rexy found herself hopelessly defeated at the hands of a larger, stronger theropod. 

The 13.5-ton Deinosuchus-Concavenator-Acrocanthosaurus-Giganotosaurus placed his foot on her limp body, roaring triumphantly towards the skies, before moving towards the humans. 

THUD. THUD. THUD. 

Zeb the Giga turned towards the thunderous footsteps...to find Big Daddy glaring holes into him. 

The new Tyrannosaurus Rex was tall enough to look Zeb straight in the eye, and he was noticeably bulkier and more robust than Rexy. Snarling in anger and frustration at the arrival of another competitor, Zeb roared aggressively, and Big Daddy responded with his own thunderous, deafening roar. 

Leaving Rexy's seemingly lifeless body alone, Zeb stomped forward to intimidate the newcomer, snapping his jaws aggressively. But far from being intimidated, Big Daddy snorted derisively. 

They circled each other like wolves, sizing each other up. Zeb definitely held the advantage in length and a very slight edge in height, but that was it. He could tell that Big Daddy would be MUCH harder to beat than the old female Rex he had brought down just now. 

The two roared a final time, before charging at each other. 

Zeb knew that the Rex would instinctively go for a bite, so he lowered his head to headbutt it away. 

Unfortunately, he miscalculated. Big Daddy met his headbutt with his own headbutt. And since Big Daddy had been specifically designed to have an overwhelmingly, immensely thick and rugose skull with maximum pachyostosis...

Searing, blinding pain shot through Zeb's skull as the force of Big Daddy's headbutt caused him to stumble back unceremoniously. He panicked; he had never been overwhelmed like this before. He shook his head trying desperately to clear the dizziness, but Big Daddy was relentless. Bowing his head, he rapidly brought it up just as quickly, ramming it into Zeb's chest from below. 

The 13-ton T-Rex flipped the 13.5-ton Giganotosaurus over onto his side, the force of the blow shattering several of Zeb's ribs. 

All the while Rexy had woken up and seen the entire fight with wide eyes...as if the arrival of a new, even larger and chonkier Rex wasn't enough, watching him near-effortlessly destroy him was even more surprising, though not unwelcome. 

As Zeb staggered to his feet, Big Daddy opened his jaws wide and tore into his right torso, tearing off not just his right arm but the entire socket and the entire chunk of his right chest. Zeb's screams of agony pierced the night, and continued to do so as Big Daddy continued to literally tear into him. 

He latched his jaws onto his neural spines, crunching down forcefully. Even Rexy winced when she saw and heard the catastrophic destruction of bones and soft tissue, Big Daddy's teeth tearing out an entire half-moon shaped chunk out of Zeb's back. 

Zeb howled as his backbone was crushed and torn out, blood spilling copiously from his chest, back and froth from his mouth. With a final, pained groan, he fell over onto his side, dead. 

Rexy #05 approached Big Daddy cautiously, who contemptuously nudged Zeb to see whether he was indeed dead. Like Rexy #03, she had never seen a male Rex before in her life. 

Big Daddy also eyed her appraisingly. Eventually, like their counterparts in another universe (and many others), they began sniffing each other to form bonds with each other. 

Alan Grant, Owen Grady and the others could only watch in trepidation as Rexy followed Big Daddy away into Biosyn Valley...although, somehow, they were never seen again despite repeated searches throughout the valley. 

Chapter Text

At dawn, Big Daddy and his female Ark Rex mate set out. But not to hunt. 

The two giant Tyrannosaurus made their way through the fields and past the rivers, through the mountains and volcanoes. As they thundered past a mountain, a mated pair of Ark Giganotosaurus saw them and roared thunderously at them. But it was not hostile; it was a greeting. 

Big Daddy and his mate turned their heads, and roared back in greeting. Ever since Big Daddy and his mate and other Rexes had helped them to eradicate a particularly hostile and dangerous competitor, the pair of Ark Gigas were grateful to them and recognized them as friends. 

Eventually, Big Daddy and Ark Rex reached their destination: the snow biomes. 

And they wasted no time frolicking in the snow, opening their mouths to taste the snowflakes and making snow angels in the snow. 

This was a precious time where they didn't need to worry about hunting. Or competitors. They could just play and relax all they wanted like children. 

No anxiety. No enemies. Just each other, and tons of fun. 

Chapter Text

Panicked roars and bellows pierced the air as the tyrannical couple struck again. 

Bryan, the PT Tyrannosaurus rex, grabbed the neck of a PT Giganotosaurus and smashed right through the muscles and bones easily with a solid bite. Letting the Giga's corpse fall to the ground, he turned to avoid the deadly lunge of a PoT Tyrannotitan. Bryan opened his jaws and grabbed the Tyrannotitan's skull, before crunching and blasting through it with a loud CRACK. 

Arya the Isle Tyrannosaurus rex, his mate, charged into the fray with a ferocious roar, grabbing an Isle Giganotosaurus's leg and exploding it with her bite force in a shower of blood and splintered bone; instantly killing another Isle Giganotosaurus by grabbing its neck and pulverizing it, and swiveling to latch her jaws around a Divine Beasts Carcharodontosaurus and with a horrifying bite decapitated it. 

As the remaining Giganotosaurus and Tyrannotitan fled, Bryan roared and pursued them, tearing off their tails, crippling their legs and even killing some of them. 

As Bryan and Arya stood over the countless corpses that stained the ground red with blood, they raised their heads and roared, announcing to everyone who could hear that yet another 500 square miles of territory was theirs. 

Chapter Text

It's been a few days since Biosyn Sanctuary was declared a global sanctuary for all prehistoric species, making it one of the largest sanctuaries today.

Currently, the sanctuary is dominated by an alpha species, the Tyrannosaurus rex. Despite having arrived relatively recently, the individuals known as "Rexy," the brown female, and "Big Daddy," the large red male, positioned themselves as the apex of the sanctuary over the course of one night, eliminating the unstable previous apex, Giganotosaurus, an individual who was crazy because he wasn't a completely pure animal but a poorly designed amalgamation. After his death, the T. Rex couple took over as apex predators.

The rex couple was resting after a midnight dinner, having feasted on a particularly massive giant Edmontosaurus. Morning was shining from the horizon. Rexy was the first to wake up, yawning and inspecting her surroundings, shaking herself a little in the humid atmosphere of the valley. She turned to look at her nest with her unhatched eggs. Then she turned to look at To her partner and father of her eggs, who had just opened his eyes and yawned, the female began to caress her partner who reciprocated by doing the same, so they both got up to start their day, while pterosaurs flew from above along with helicopters with new rescued dinosaurs.

Phoenix International wanted to prove that their asset, Big Daddy, was the juggernaut they'd been waiting for, and for whom they'd invested so much on. To prove it, they went to Site B after one of their agents informed them of a supposed "T-Rex Killer" living on Isla Sorna, a Spinosaurus.
So they set off, managing to track and capture Big Daddy and take him to the transport ship. After a few hours of travel, they reached their destination.

Lowering the floodgates, they freed the large carnivore. Using a company all-terrain vehicle, they guided him into the jungle while drones followed them. Big Daddy managed to reach the all-terrain vehicle and destroyed it simply by stomping on it, killing almost all the passengers except one.

The rex was disoriented in this new place but through its sense of smell it detected some herbivores nearby so it went to fill its stomach. After killing two Parasaurolophus and devouring a little, the rex felt an unwelcome presence coming for it, from the nearby river a sail appeared from there so that the intruder came to the surface. The infamous rex killer, the Spinosaurus, had arrived with the intention of usurping its throne.

Big Daddy, giving a groan of frustration & annoyance, stomped forward with a ferocious growl ready to fight. The Spino didn't hesitate and launched himself for the first blow, but Big Daddy responded with a ferocious tackle that knocked the wind out of the Spino, shoving it several meters back. As the Spino tried to recover its bearings, Big Daddy charged with his jaws open and grabbed the usurper's neck. Muscles were obliterated, and bones were thoroughly pulverized & smashed through with ease. With one solid bite, Big Daddy instantly ended the fight, pulverizing & destroying the Spinosaurus's neck. All the onlookers, whether at the scene or via remote-controlled cameras were stunned into silence at how short the "fight" was, but it made the power of the crimson T. Rex clear. It was every bit the juggernaut & destroyer Phoenix International intended it to be. 

In another universe, Big Daddy existed as a mini-Kaiju Brute Wyvern in a Monster Hunter universe. And what a beast he was - 43 meters long and 14.5 meters tall at the hips. He fought the Elder Dragon Primordial Malzeno once - and thoroughly defeated it. He claimed the Elder Dragon Lao-Shan-Lung's territory for himself after swiftly killing it with a crushing, pulverizing bite to the head. And Raging Brachydios...was little more than a nuisance. 

He loved sparring with the 41-meter long Worldeater Deviljho. In the heat of battle, the giant Deviljho would swell up his muscles and charge his body up with Dragon element. Big Daddy did the same, unleashing his Destroyer state where his muscles swelled up immensely, glowing a menacing red. Their beamclashes of explosive Dragon element had annihilated whole rock formations and even entire mountainsides before.

And there was that one time Brute Wyvern Big Daddy entered the ARK universe...not even the Giganotosaurus's Rage Mode could save itself from Big Daddy's berserker fury. Using his insane leaping abilities that rivalled that of Deviljho, Big Daddy had grabbed the Giganotosaurus's neck and flailed it, thrashed it and slammed it around in uncontained rage that the Rage Mode Giganotosaurus was helpless to, before he had finally smashed through the neck and decapitated it with a savage, triumphant roar. 

Legends say there exists a mini-Kaiju version of Big Daddy, one whose power seemed to know no limit. 

When the warlords of ARK lead a foursome of wild ARK Carcharodontosaurus and a fivesome of ARK Giganotosaurus against it, this colossal crimson Tyrant King held its own...and the four Carcharodontosaurus and five Giganotosaurus lay dead at its feet, their heads exploded & smashed to little more than a pulp, and more often than not separated from their bodies. 

The results did not change with a new force of five Paleo ARK Giganotosaurus and five Paleo ARK Carcharodontosaurus. The Great Destroyer remained undefeated, unbeatable, invincible. 

When Big Daddy entered the world of Monster Hunter, no one but the three Forbidden Monster tier Elder Dragons dared to challenge it. 

Safi'jiiva was the first to fall, his head popped like a grape under the Tyrant King's absurdly destructive bite power. 

Alatreon was the next to fall, a massive gaping hole blasted through his chest by Big Daddy's concentrated beam of Dragon element. 

Until the only one who could fight him was the infamous Black Dragon, Fatalis himself. 

Fatalis attacked in the trademark way he knew to attack, his Kalpa'agni, his giant scorching flames. Big Daddy responded with his own colossal inferno of scorching flames, the clash emitting such heat and light it was as though the sun was going to fall to the ground. 

When neither would give way, Fatalis turned up the heat...quite literally. Stretching his wings even wider outwardly, his blast became vastly more destructive and powerful, with the intent of utterly demolishing and torching Big Daddy alive. 

However, Big Daddy countered by also turning up the heat, gathering up his flames into a colossal, gargantuan fireball of roiling, scorching flames which he let loose towards the Black Dragon. 

As the gigantic Fire Scorcher continued to sail towards Fatalis, the flames of the Kalpa'agni showing no visible effect of stopping the giant miniature sun of death, one could only wonder what the outcome of this battle would be.