Pierce (Dawn of the Dinosaurs)

Pierce is an adult male Kentrosaurus that appeared in Dawn of the Dinosaurs. At first he was sour, cranky, ill-tempered, cynical, wrathful, grouchy, sarcastic, grumpy, surly, angry, lonely, cold and stubborn, but at the end, he becomes kind, selfless, heroic, kind-hearted, brave and nice.

Meeting Rick, Brill and Hallo
Pierce embittered by his experiences, ignored the crowds of dinosaurs migrating south to escape the freezing cold brought on by the ice age as he walked right through them all, not caring that he was nearly stepping on some of them, until amphibian, a single Koolasuchus father, shouted at Pierce, calling him out on his slow pace and blocking the road ahead, to which Pierce coldly responded by calling out the shortness of the Koolasuchus' head and how the start was drawing attention to himself. Timidly, the Koolasuchus asked to be left to pass by with his family: Pierce dismissively let the start pass and continued to live each other, ignoring the male Koolasuchus's statement to his own family that Manfred would starve to death.

Further down the road, Pierce stood atop a ledge alone, until a small Eoraptor named Hallo ran into him, asking to be hidden from two angry Pachycephalosaurus named Brone & Moldu. The two Pachys intended to brutalize Hallo for ruining their meal, which Pierce was indifferent towards, but Hallo, seeking protection, hid behind the Kentrosaurus's legs. Pierce stayed indifferent and brought up that pachys were herbivorous, to which Moldu pointed out that they'd kill Hallo out of fun, which displeased Pierce. This did not register with the pachys, who still wished to harm the Eoraptor, and Pierce, bluffing, told the pachys that if they crossed the sinkhole dividing them, they might take Hallo. Hallo, overconfident in his safety, called out another bluff, throwing a rock at them, which landed on the sinkhole, which had since dried up, revealing the bluff.

The two pachys rushed at Pierce and Hallo, and Pierce used his tail to stave the pachys off, shoving them back onto the ground, when Brone rushed in to charge Hallo, but Pierce seized the Pachy by his horn and flung him around, throwing Brone. Moldu also rushed in, stampeding towards Hallo when Pierce scooped the Pachy in his tusks and threw him aside. Hallo, happy to see that the pachys were halted, rushed to hug Pierce, causing the kentrosaurus to lose his footing and slide down the ledge, no worse for wear. Hallo landed to Pierce head, when Rick, a Utahraptor, and Brill, a Dimorphodon, saw them both, when he got up; Rick went to Pierce, offering to join him, along with Brill and Hallo. Pierce sarcastically invited Rick, Brill and Hallo travel through the whole journey north rather than south before coldly leaving the Dimorphodon and Eoraptor. Hallo, thinking he was safe, thanked Pierce for his help and set off alone. Within a moment of hearing the Pachycephalosaurus threaten him, Pierce, seeing that Hallo really wanted protection from any threats, paid the Eoraptor no mind, but Hallo, intending to latch on, insisted on joining the Kentrosaurus, along with Rick and Brill.

Further up north, The group found an area to rest for the night, with Pierce carrying a number of large logs with his back and Hallo dragging one stick as though it were heavy. Pierce skeptically asked Hallo whether one stick was enough to make shelter, but Hallo had another plan: he would snap the stick in two and make fire with it.

That night, however, the rains fell thick and fast, leaving Hallo out in the cold, still rubbing the two sticks together out in the rain while Pierce, Rick and Brill lay in a shelter they fashioned from the logs. To fool Hallo as a joke, Rick claimed to see a spark, which worked, as Hallo looked happily for a moment. Hallo decided to stop trying to make fire and asked The trio if he might squeeze in the shelter, but Brill was not interested in sharing the shelter. While out in the rain, Pierce, Rick and Brill, having a soft spot touched, went to sleep in shelter, away from Hallo.

More to be added.

Pre-2016
A Kentrosaurus was cloned some time during or before 2016 on a secret island owned by Mantah Corp by Dr. Mae Turner, a paleo-neurobiologist that named the stegosaur "Pierce". Mae raised Pierce and kept him within a desert biodome, alongside a Smilodon. There she studied his brain reactions and found a way to somewhat communicate with him via replaying Pierce' own sounds back at him once she could understand what they meant on a basic level.

Mantah Corp Incident
One day in the summer of 2016, Kash D. Langford ordered Pierce to be moved into their arctic biodome while being monitored by a BRAD robot in order to see how long the dinosaur can survive in such conditions. In the middle of the test, Mae and a group of children who had become stuck on the island stumbled upon the dying Kentrosaurus, and decided to help Mae move him back to the desert biodome he belongs in via moving him onto metal cots and pulling them with snow gliders. The plan works until the BRAD monitoring Pierce attacks the vehicles in order to stop their interference with the test. The confrontation ends with Yasmina Fadoula kicking the robot into a frozen lake they had been forced to drive over, allowing the group to move Pierce to the tunnels in between the domes where he could warm up.

With the immediate danger over, Mae and the kids moved Pierce back into the desert biodome, where Mae demonstrated her ability to communicate with the dinosaur on a basic level and allowed Darius Bowman to attempt this, although Pierce wasn't as appreciative towards them as he was to Mae's attempts.

The following day, Kash forced Pierce into another test, this time for him to fight a Tyrannosaurus rex named Big Eatie. While the pair was unwilling to fight initially, the drones forcing them closer together with electric shocks eventually forced them into it.

As the pair fought on, Pierce began to wear out against his larger opponent, breaking a tail spine within the Tyrannosaurus and eventually being taken out of the fight with a heavy injury. At this time, Darius Bowman had attempted to stop the fight, but was distracted by a phone he could use to contact the mainland before being caught by Kash, whom he convinced to spare the animals after pointing out how rare and expensive they are. Kash then sent drones out to separate the combatants and take them both down to the medical facility, although he believed Pierce likely wouldn't survive his injuries.

After Darius escaped from Kash, he snuck into the facility's main base and overheard Kash speaking with his boss about food supplies for the island's new Dilophosaurus running low, with the boss stating they will feed Pierce to the dinosaurs. With this knowledge, Darius hatched a plan to save Pierce, with Mae and Ben Pincus attempting to save him, only to be forced onto the feeding platform by an overwhelming amount of BRADs. As the feeding platform forced them into the biodome, they were quickly surrounded by Dilophosaurus, only for more of the kids to arrive with a snow glider to chase them off. As the group began celebrating, they were surrounded again, this time by BRAD-Xs as Kash and the boss revealed the entire plot was a trap to catch the group.

Trivia

 * Pierce is the only one herbivore dinosaurs that fight with Spinosaurus.
 * He is the only one Kentrosaurus in the world.