Indominus Rex is a new attraction and main antagoist in Jurassic World. The hybrid was created by combining the genetic traits of multiple species. Some of the known species that were used in the creation of the hybrid are Tyrannosaurus, Velociraptor, Carnotaurus, Giganotosaurus, Majungasaurus, and Rugops, as well as modern animals like cuttlefish and an unknown type of Tree frog.
InGen's chief scientist, Dr. Henry Wu, was fascinated with the possibility to create entirely new species by gene mixing, ever since he learned that the inclusion of frog DNA had given the dinosaurs the ability to switch gender. In 1997, he created a hybrid plant.
Years after its opening, the success of the park Jurassic World started to wane and the investors got worried. Masrani's Chief Operations Officer described the 2013 success as merely acceptable. "The world has seen what we have to offer, but they aren't in awe as they once used to be. We need to change that. You can't expect the world's greatest theme park to merely rely on the same attractions. We need to be proactive, thinking of bigger and better things."
Masrani decided to expand Henry Wu's work on hybrids and create a new dinosaur that was bigger, more intelligent and more dangerous than any other dinosaur in the park. Development of the hybrid began in 2012 in the Hammond Creation Lab. Upon Simon Masrani's announcement of the creation of the genetic hybrid, Indominus rex, online ticket sales for Jurassic World skyrocketed.
The hybrid could run up to speeds of 30 mph with its roar alone reaching 140db-160db, as loud as the liftoff and landing of a Boeing 747 airplane. Indominus rex had osteoderms across its body and horn-like decorations above its eye orbits, traits that originated from the abelisaurs used in its creation. It also had well-developed forelimbs complete with opposable thumbs that I. rex used to grab prey and get in quadrupedal stances. It was able to change color from the cuttlefish used in its creation, which was used as camouflage in hunting. The tree frog DNA had allowed it to detect thermal signatures and even remove her own thermal scent. Finally, the Velociraptor DNA used in Indominus' creation gave it a high level of intelligence as well as the ability to communicate with Velociraptor individuals.
Though they do hunt for survival purposes, Owen Grady, a Velociraptor trainer, says he has exhibited the hybrid hunting for sport. However, since the I. rex who had exhibited these traits had a rough upbringing this behavior may not be natural.
I. rex was kept in their own paddock that had 12 meter (40 feet) high walls. The Indominus that was placed there became deranged from having no social interaction with other members of her species and not enough space in her paddock. Her creators decided to make a sibling for her just in case she died, however, this sibling was later killed by the first inhabitant of the paddock. This Indominus would also attack her paddock workers as well. Three weeks before their paddock was open to the public, Simon Masrani told Claire Dearing to consult Owen Grady to see if he was interested in taking a job requiring him to inspect the Indominus rex Paddock for any vulnerabilities.
That same day, the Indominus later managed to avoid her temperature being picked up by the thermal cameras and leaving scratch marks on the walls to make them think she was able to climb over the enclosure's wall. Once they realize, they run and she manages to break through the door as it has not fully shut. After her escape, she went on a rampage throughout the Jurassic World park. When Owen Grady and a Timack Construction worker were investigating the damaged paddock the hybrid took the opportunity to attack them. The I. rex managed to kill the construction worker, but Owen evaded her by hiding under a nearby car outside of her paddock by cutting its fuel tank, masking his scent. Though, she was unable to find Owen, she did kill the paddock supervisor.
Her escape was not reported to Jurassic World visitors because Simon Masrani thought the Asset Containment Unit would capture her by following her tracker implant. The I. rex traveled south of her paddock having detected the thermal signatures of the visitors in Main Street. She removed her tracker and ambushed the team. killing most of the troopers, including Katashi Hamada, Craig, and possibly other members of the team. She then went into the Gyrosphere attarction and attacked brothers Zach and Gray Mitchell who were observing 4 Ankylosaurus. In her attack, she agitated one of the Ankylosaurus who proceeded to fight back against her though her counterattack ended with her being killed by the Indominus. She resumed attacking the two brothers, but the two brothers escaped her by getting out of their damaged Gyrosphere and jumping off a waterfall.
Afterward, the Indominus attacked a herd Apatosaurus, killing five and fatally injuring one before moving on into the restricted area of Isla Nublar. While in the restricted area, the I. rex discovered Owen and Claire Dearing inside the Visitor Center to which she took the opportunity to attack and chase them. However, her pursuit of the humans ended when she saw the JW001 piloted by Masrani outfitted with a heavy machine gun in pursuit of her. She led her pursuer to the Jurassic World Aviary where she smashed through the enclosure's walls and scarred the pterosaurs inside out of the aviary to the open hole she created. As the freed pterosaurs lead to the destruction of JW001 and attacked the guests in Main Street, the Indominus traveled further into the restricted area of the island.
That night in the restricted area the members of Jurassic World's Velociraptor pack found her. However, she communicated with the raptors and became the alpha of their pack. As the leader of the pack, she commanded the raptors that were under her control to attack the humans that came with them and were in the area, to which they followed this order. Upon the initiation of this order, the InGen Security troopers, Owen, and Barry, who were following the Velociraptors opened fire on the hybrid. She managed to escape the brawl the firefight that ensued as the small arms fire had little to no effect on her, but she did nearly collapse on the ground when she was hit by rocket from one of the troopers while escaping.
The I. rex finally arrived in Main Street where she met Owen, Claire, the Mitchell brothers and the three remaining raptors once again. The raptors, now aligned with Owen's group again, proceeded to attack the Indominus with Owen Grady providing suppressive fire with his rifle. But the fight ends fairly quickly as she easily kills raptors Delta, Echo, and seemingly Blue. With the raptors defeated, the Indominus rex then proceeds to resume hunting Owen and the Mitchell brothers who are huddled inside one of Main Street's shops. She nearly drags Gray to her but is stopped by another dinosaur who challenges her: Rexy, Jurassic World's Tyrannosaurus rex.
Rexy carries out a heavy assault on Indominus, but Rexy is eventually brought to the ground by the hybrid's strength. The Indominus almost delivers the killing blow before she is then attacked by Blue who is still alive from the onslaught. This allows Rexy to return to her feet and grab the I. rex by the neck, pushing her into many of Main Street's building all while Blue continues biting and scratching her. Finally, she is flung to the edge of the Jurassic World Lagoon where the Mosasaurus there detects the hybrid and proceeds to pull her under the water.
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